Kenya Westgate siege
Armed police search Westgate Shopping Centre in Nairobi - (Reuters)

The Islamist militants who stormed the Westgate mall in Nairobi are suspected to be accessing the internet inside the shopping centre tracking all the latest developments in the outside world including the security measures.

The al-Shabab militants have forced the Kenya National Disaster Operation Centre to shut down its social media updates regarding the rescue operation.

"Social media updates from the scene are now suspended. Hostiles suspected to have access to the internet," said the centre on its Twitter account.

Neither the number of hostages nor the exact number of attackers inside the mall is known.

Earlier, Twitter had also blocked al-Shabab's account from posting updates. Following the Somali militant outfit's claim over the responsibility for the attack, the @HSM_Press account was taken off cyberspace.

The group wrote on its account: "The 10 hours have passed and the Mujahideen are still strong inside Westgate Mall and still holding their ground. All praise is due to Allah!"

Another message said: "For long we have waged war against the Kenyans in our land, now it's time to shift the battleground and take the war to their land."

According to the micro-blogging site's policies, users will be banned "for unlawful purposes or in furtherance of illegal activities".

Al-Shabab's earlier Twitter accounts under the names @HSMPress and @HSMPress1 were also blocked on previous occasions.

Meanwhile, the disaster management centre said one person has been released from the mall while the standoff with the insurgents continues.

It has nearly been 22 hours since the militants entered the mall while bursts of gunfire have been frequently heard.