Soldiers on an American tank shot at Dana on Sunday while he filmed outside Abu Ghraib prison in western Baghdad which had earlier come under a mortar attack, witnesses said.

The New York-based Committee to Protect Journalists (CPJ) and Reporters Sans Frontieres (Reporters Without Borders, RSF) in Paris urged the U.S. authorities to conduct a full inquiry.

Dana, a 43-year-old Palestinian, had worked for Reuters mostly in the West Bank city of Hebron. The CPJ honored him with its International Press Freedom Award in 2001 for his work in Hebron where he was wounded and beaten many times.

"In the midst of frequent violence, and often under attack himself, Mazen was a determined witness who took constant risks in order to tell the world the news from the West Bank -- and more recently from Iraq," CPJ executive director Ann Cooper said in a statement on the committee's Web site.

The statement said the CPJ "calls for a full investigation into the shooting and a public accounting of the circumstances."

"We are shocked and extremely disturbed by this new death," Severine Cazes of RSF told CNN television. "There have been many mistakes...by the U.S. military during the war."

The group would be writing to Defense Secretary Donald Rumsfeld on Monday to seek a fuller investigation than those inquiries made into previous incidents in Iraq, Cazes said.

"It's disappointing to see that a country which is a big democracy, which respects freedom of the press and which is waging a war in the name of those values is not able to do proper investigations," she said.

RSF urged Rumsfeld to launch an "honest investigation that will not lead to just a whitewash of the U.S. military."

The U.S. armed forces said on Sunday that their troops had "engaged" a Reuters cameraman. It said soldiers had thought his camera was a rocket-propelled grenade launcher.

Reuters Chief Executive Tom Glocer has called for "the fullest and most comprehensive investigation into this terrible tragedy."

Dana is the second Reuters cameraman to be killed since the U.S.-led force invaded Iraq to topple Saddam Hussein. His death brought to 17 the number of journalists or their assistants who have died in Iraq since the war began on March 20.