Latest reports from inside the besieged Westgate shopping centre in Nairobi suggest that the Somali al-Shabaab militants who laid siege to the mall on Saturday continue to occupy the building, and have taken an unknown number of hostages.

Overnight, Somalia's al-Qaida-linked rebel group, al-Shabaab, claimed responsibility for the attack, in which they targeted non-Muslims.

Fifty-nine people are thought to have died so far, and many more have been injured.

Kenya's interior cabinet secretary Joseph Lenku said about 1,000 people have been rescued so far from the mall.

The gunmen remain inside with their hostages.

The militants are thought to be accessing the internet inside the shopping centre, tracking all the latest developments in the outside world, including security measures.

Below are the latest images from in and around the shopping centre. WARNING: SOME READERS MAY FIND GRAPHIC IMAGES BELOW DISTURBING.

READ MORE: 300 Feared Dead and Injured in Mall Siege

Nairobi Westgate Mall Siege, Day 1 in Pictures (WARNING: GRAPHIC IMAGES)

Civilians escape an area at the Westgate Shopping Centre in Nairobi September 21, 2013. Gunmen stormed the shopping mall in Nairobi on Saturday killing at least 20 people in what Kenya's government said could be a terrorist attack, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Sporadic gun shots could be heard hours after the assault started as soldiers surrounded the mall and police and soldiers combed the building, hunting down the attackers shop by shop.
Civilians escape an area at the Westgate Shopping Centre in Nairobi September 21, 2013. Gunmen stormed the shopping mall in Nairobi on Saturday killing at least 20 people in what Kenya's government said could be a terrorist attack, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Sporadic gun shots could be heard hours after the assault started as soldiers surrounded the mall and police and soldiers combed the building, hunting down the attackers shop by shop.Reuters/Siegfried Modola
A general view shows cars parked at the Westgate shopping mall during a shootout between armed men and the police in Nairobi September 22, 2013. Kenyan security forces were locked in a stand-off on Sunday with gunmen who killed at least 39 people at the upmarket shopping mall in the Kenyan capital, and it was still unclear how many hostages the al Qaida-linked militants were holding.
A general view shows cars parked at the Westgate shopping mall during a shootout between armed men and the police in Nairobi September 22, 2013. Kenyan security forces were locked in a stand-off on Sunday with gunmen who killed at least 39 people at the upmarket shopping mall in the Kenyan capital, and it was still unclear how many hostages the al Qaida-linked militants were holding.Reuters/Thomas Mukoya
A police officer tries to secure an area inside the Westgate Shopping Centre where gunmen went on a shooting spree in Nairobi September 21, 2013. The gunmen stormed the shopping mall in Nairobi on Saturday killing at least 20 people in what Kenya's government said could be a terrorist attack, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Sporadic gun shots could be heard hours after the assault started as soldiers surrounded the mall and police and soldiers combed the building, hunting down the attackers shop by shop. Some local television stations reported hostages had been taken, but there was no official confirmation.
A police officer tries to secure an area inside the Westgate Shopping Centre where gunmen went on a shooting spree in Nairobi September 21, 2013. The gunmen stormed the shopping mall in Nairobi on Saturday killing at least 20 people in what Kenya's government said could be a terrorist attack, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Sporadic gun shots could be heard hours after the assault started as soldiers surrounded the mall and police and soldiers combed the building, hunting down the attackers shop by shop. Some local television stations reported hostages had been taken, but there was no official confirmation.Reuters/Siegfried Modola
A mother and her children hide from gunmen at Westgate Shopping Centre in Nairobi September 21, 2013. Gunmen stormed the shopping mall in Nairobi on Saturday killing at least 20 people in what Kenya's government said could be a terrorist attack, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Sporadic gun shots could be heard hours after the assault started as soldiers surrounded the mall and police and soldiers combed the building, hunting down the attackers shop by shop.
A mother and her children hide from gunmen at Westgate Shopping Centre in Nairobi September 21, 2013. Gunmen stormed the shopping mall in Nairobi on Saturday killing at least 20 people in what Kenya's government said could be a terrorist attack, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Sporadic gun shots could be heard hours after the assault started as soldiers surrounded the mall and police and soldiers combed the building, hunting down the attackers shop by shop.Reuters/Siegfried Modola
Civilians escape an area at the Westgate Shopping Centre in Nairobi September 21, 2013. Gunmen stormed the shopping mall in Nairobi on Saturday killing at least 20 people in what Kenya's government said could be a terrorist attack, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Sporadic gun shots could be heard hours after the assault started as soldiers surrounded the mall and police and soldiers combed the building, hunting down the attackers shop by shop.
Civilians escape an area at the Westgate Shopping Centre in Nairobi September 21, 2013. Gunmen stormed the shopping mall in Nairobi on Saturday killing at least 20 people in what Kenya's government said could be a terrorist attack, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Sporadic gun shots could be heard hours after the assault started as soldiers surrounded the mall and police and soldiers combed the building, hunting down the attackers shop by shop.Reuters/Siegfried Modola
People run for cover as the stand-off continues into the night at Westgate Shopping Centre in Nairobi September 21, 2013. Gunmen stormed the shopping mall in the Kenyan capital Nairobi on Saturday, killing at least 30 people including children and sending scores fleeing in panic, in an attack claimed by the Somali Islamist group al Shabaab. Shooting continued hours after the initial assault as troops surrounded the Westgate mall and police and soldiers combed the building, hunting the attackers shop by shop. A police officer inside the building said the gunmen were barricaded inside a Nakumatt supermarket, one of Kenya's biggest chains.
People run for cover as the stand-off continues into the night at Westgate Shopping Centre in Nairobi September 21, 2013. Gunmen stormed the shopping mall in the Kenyan capital Nairobi on Saturday, killing at least 30 people including children and sending scores fleeing in panic, in an attack claimed by the Somali Islamist group al Shabaab. Shooting continued hours after the initial assault as troops surrounded the Westgate mall and police and soldiers combed the building, hunting the attackers shop by shop. A police officer inside the building said the gunmen were barricaded inside a Nakumatt supermarket, one of Kenya's biggest chains.Reuters/Noor Khamis
A dead man lies at the entrance of the Westgate Shopping Centre in Nairobi September 21, 2013. Militant gunmen stormed the shopping mall in Nairobi on Saturday killing at least 25 people, including children, and sending scores fleeing in panic from shops and restaurants on to the streets, according to witnesses and the Red Cross.
A dead man lies at the entrance of the Westgate Shopping Centre in Nairobi September 21, 2013. Militant gunmen stormed the shopping mall in Nairobi on Saturday killing at least 25 people, including children, and sending scores fleeing in panic from shops and restaurants on to the streets, according to witnesses and the Red Cross.Reuters/Siegfried Modola
A policeman patrols with his dog near the Westgate Shopping Centre in Kenya's capital Nairobi September 22, 2013. Kenyan security forces were locked in a stand-off on Sunday with gunmen who killed at least 39 people at an upmarket shopping mall in the Kenyan capital, and it was still unclear how many hostages the al Qaeda-linked militants were holding.
A policeman patrols with his dog near the Westgate Shopping Centre in Kenya's capital Nairobi September 22, 2013. Kenyan security forces were locked in a stand-off on Sunday with gunmen who killed at least 39 people at an upmarket shopping mall in the Kenyan capital, and it was still unclear how many hostages the al Qaeda-linked militants were holding.Reuters/Thomas Mukoya
A wounded man sits screaming in shock at a parking lot of Westgate Shopping Centre in Nairobi September 21, 2013. Militant gunmen stormed the shopping mall in Nairobi on Saturday killing at least 39 people, including children, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Kenyan security forces were still locked in a standoff on Sunday with the al Qaeda-linked militants, who were holding an unknown number of hostages. Picture taken September 21, 2013.
A wounded man sits screaming in shock at a parking lot of Westgate Shopping Centre in Nairobi September 21, 2013. Militant gunmen stormed the shopping mall in Nairobi on Saturday killing at least 39 people, including children, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Kenyan security forces were still locked in a standoff on Sunday with the al Qaeda-linked militants, who were holding an unknown number of hostages. Picture taken September 21, 2013.Reuters/Goran Tomasevic
Policemen search a man for weapons as he walked out of Westgate Shopping Centre in Nairobi September 21, 2013. Militant gunmen stormed the shopping mall in Nairobi on Saturday killing at least 39 people, including children, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Kenyan security forces were still locked in a standoff on Sunday with the al Qaeda-linked militants, who were holding an unknown number of hostages. Picture taken September 21, 2013.
Policemen search a man for weapons as he walked out of Westgate Shopping Centre in Nairobi September 21, 2013. Militant gunmen stormed the shopping mall in Nairobi on Saturday killing at least 39 people, including children, and sending scores fleeing into shops, a cinema and onto the streets in search of safety. Kenyan security forces were still locked in a standoff on Sunday with the al Qaeda-linked militants, who were holding an unknown number of hostages. Picture taken September 21, 2013.Reuters/Goran Tomasevic
A man donates blood at a temporary donation centre for the injured victims of a crossfire between armed men and the police at the Westgate shopping mall, in Kenya's capital Nairobi September 22, 2013. Islamist militants were holed up with hostages on Sunday at a shopping mall in Nairobi, where at least 59 people have been killed in an attack by the al Shabaab group that opposes Kenya's participation in a peacekeeping mission in neighboring Somalia.
A man donates blood at a temporary donation centre for the injured victims of a crossfire between armed men and the police at the Westgate shopping mall, in Kenya's capital Nairobi September 22, 2013. Islamist militants were holed up with hostages on Sunday at a shopping mall in Nairobi, where at least 59 people have been killed in an attack by the al Shabaab group that opposes Kenya's participation in a peacekeeping mission in neighboring Somalia.Reuters/Thomas Mukoya
Volunteers at the MP Shah hospital assist a man whose relative was killed in Saturday's attack at the Westgate shopping mall in Nairobi September 22, 2013. Kenyan security forces were locked in a stand-off on Sunday with gunmen who killed at least 59 people at the upmarket shopping mall in the Kenyan capital, and it was still unclear how many hostages the al Qaeda-linked militants were holding.
Volunteers at the MP Shah hospital assist a man whose relative was killed in Saturday's attack at the Westgate shopping mall in Nairobi September 22, 2013. Kenyan security forces were locked in a stand-off on Sunday with gunmen who killed at least 59 people at the upmarket shopping mall in the Kenyan capital, and it was still unclear how many hostages the al Qaeda-linked militants were holding.Reuters/Thomas Mukoya
Members of the Indian community pay their respects at the cremation ceremony of Nehal Vekaria, a 16-year-old female student who was killed during the shooting spree at the Westgate Shopping Centre, in Nairobi September 22, 2013. Islamist militants were holed up with hostages on Sunday at a shopping mall in Nairobi, where at least 59 people have been killed in an attack by the al Shabaab group that opposes Kenya's participation in a peacekeeping mission in neighboring Somalia.
Members of the Indian community pay their respects at the cremation ceremony of Nehal Vekaria, a 16-year-old female student who was killed during the shooting spree at the Westgate Shopping Centre, in Nairobi September 22, 2013. Islamist militants were holed up with hostages on Sunday at a shopping mall in Nairobi, where at least 59 people have been killed in an attack by the al Shabaab group that opposes Kenya's participation in a peacekeeping mission in neighboring Somalia.Reuters/Noor Khamis
Relatives and Muslim faithful bury the slain body of Rehmad Mehbub, 18, who was killed in a crossfire between armed men and the police at the Westgate shopping mall, in Kenya's capital Nairobi September 22, 2013. Islamist militants were holed up with hostages on Sunday at a shopping mall in Nairobi, where at least 59 people have been killed in an attack by the al Shabaab group that opposes Kenya's participation in a peacekeeping mission in neighbouring Somalia.
Relatives and Muslim faithful bury the slain body of Rehmad Mehbub, 18, who was killed in a crossfire between armed men and the police at the Westgate shopping mall, in Kenya's capital Nairobi September 22, 2013. Islamist militants were holed up with hostages on Sunday at a shopping mall in Nairobi, where at least 59 people have been killed in an attack by the al Shabaab group that opposes Kenya's participation in a peacekeeping mission in neighbouring Somalia.Reuters/Thomas Mukoya