Tributes have been paid to the five police officers who were shot dead by a lone gunmen at a protest in Dallas. Senior Corporal Lorne Ahrens, Michael Krol, Sergeant Michael Smith, Police Officer Patrick Zamarripa, and Police Officer Brent Thompson, of the Dallas Area Rapid Transit Police Department lost their lives in the line of duty on 7 July after Micah Johnson opened fire at the Black Lives Matter rally in a targeted attack.

Seven more officers were injured. The tragedy has been called the deadliest day for police officers since 9/11.

As the people of Dallas come to terms with the tragedy, memorials and vigils have been held across the city. People gathered at Thanks-Giving Square in Dallas, Texas, to hold a faith vigil which was attended by Dallas Police Chief David Brown.

A makeshift memorial has been constructed outside the Dallas Police Headquarters where two police cars are adorned with flowers and messages in honour of the officers.

Police recruits attending their graduation ceremony at LAPD Headquarters wore black ribbons across their badges as a mark of respect.

Dallas Police Shootings
The five police officers shot and killed by a sniper during a protest in Dallas have been named as Police Officer Brent Thompson, Police Officer Patrick Zamarripa, Michael Krol, Sergeant Michael Smith and Senior Corporal Lorne Ahrens Wayne Sheriff's County

Social media is flooded with tributes to the police officers, from their grieving families and friends and from fellow officers from police forces across the US. Meanwhile, celebrities unite to call for an end to the violence.

President Barack Obama has ordered U.S. flags to be flown at half-staff at the White House and public facilities throughout the U.S until sunset, July 12, 2016.

Speaking at a NATO meeting in Warsaw, Poland President Obama said: "The entire city of Dallas is grieving. Police across America, which is a tight-knit family, feels this loss to their core. And we're grieving with them."

Dallas Police Shootings
A man holds a sign reading 'We Stand With You Dallas' during a vigil at Thanks-Giving Square in Dallas, Texas, on July 8, 2016, following the shootings during a peaceful protest on July 7 which left 5 police officers dead. AFP/Getty
Dallas Police Shootings
People gather to hold a faith vigil at Thanks-Giving Square in Dallas, Texas, on July 8, 2016 AFP/Getty
Dallas Police Shootings
People write condolence notes and lay flowers at a memorial in front of the Dallas Police Headquarters AFP/Getty
Dallas Police Shootings
Tributes are left for the five police officers killed by lone gunman Michah Johnson during the Black Lives Matter rally in Dallas on July 7 AFP/Getty
Dallas Police Shootings
A toy police car is placed among the flowers adorning a memorial outside the Dallas Police Headquartersin honour of five policeman who gave their lives in the line of duty AFP/Getty
Dallas Police Shootings
Snoop Dogg and fellow rapper The Game led a peaceful demonstration to police headquarters as a graduation ceremony for new recruits was underway in what they called an effort to promote unity in the aftermath of the deadly shootings of police officers in Dal AFP/Getty
Dallas Police Shootings
With black ribbons across their badge and holding a gun, police recruits attend their graduation ceremony at LAPD Headquarters AFP/Getty
Dallas Police Shootings
A police officer talks with a boy at the memorial at Dallas Police Headquarters on July 8, 2016. AFP/Getty
Dallas Police Shootings
People united in prayer at a faith vigil at Thanks-Giving Square in Dallas, Texas on July 8, 2016, AFP/Getty
Dallas Police Shootings
A woman displays a 'Dallas' tattoo at a growing memorial in front of the Dallas Police Headquarters AFP/Getty
Dallas Police Shootings
A man sells T-shirts with the poignant message 'Police lives matter' AFP/Getty
Dallas Police Shootings
A U.S. flag flies at half-staff above the White House July 8, 2016 in Washington, DC. President Barack Obama has ordered U.S. flags to be flown at half-staff at the White House and public facilities throughout the U.S until sunset, July 12, 2016. AFP/Getty