Reuters cameraman Mazen Dana, an award winning journalist who had covered some of the world's hotspots, was shot dead on Sunday on the outskirts of Baghdad, the London-based news agency said.

Soldiers on an American tank shot Dana, 43, as he filmed outside Abu Ghraib prison in western Baghdad, witnesses said.

According to CNN, his last pictures show a US tank driving towards him outside the prison walls. Several shots ring out from the tank, and Dana's camera falls to the ground.

"Army soldiers engaged an individual they thought was aiming an RPG (rocket-propelled grenade) at them. It turned out to be a Reuters cameraman," navy captain Frank Thorp, a spokesman for the chairman of the Joint Chiefs of Staff, told Reuters in Washington.

Journalists had gone to the prison after the US military said a mortar bomb attack there a day before had killed six Iraqis and wounded 59.

"Mazen was one of Reuters' finest cameramen and we are devastated by his loss. He was a brave..." said Stephen Jukes, Reuters' global head of news, in a statement.

A US military statement issued in Baghdad confirmed 'a fatal accident involving a civilian at Abu Ghraib prison' and said an investigation was underway.