©Associated Press/Narciso Contreras Contreras’s image, showing the unique version (top) and the altered version (bottom) with a circle highlighting the alteration.

Associated Press (AP) has severed ties with freelance photographer Narciso Contreras for altering a news photograph he shot in Syria, the wire service has announced. Contreras was section of a team of AP photographers that shared the Pulitzer Prize last year for coverage of the Syrian civil war.

AP reports that Contreras “recently told its editors that he manipulated a digital picture of a Syrian rebel fighter taken last September.” The picture shows the rebel fighter taking cover in a rugged landscape. Contreras altered the picture by removing from the scene a video camera sitting at the ground near the soldier.

Santiago Lyon, AP’s director of photography, said the alteration “involved a corner of the picture with little news importance,” but it surely was nevertheless a breach of AP’s standards. “Deliberately removing elements from our photographs is totally unacceptable,” Lyon said.

AP says the altered image was not a part of AP’s Pulitzer Prize-winning portfolio.

Contreras said he removed the video camera from the picture in question because he thought it should distract viewers, consistent with the AP report.

“I took the incorrect decision once I removed the camera … i believe ashamed about that,” he said. “You can battle through my archives and you’ll find that this can be a single case that happened probably at one very stressed moment, at one very difficult situation, but yeah, it happened to me, so i must assume the results.”

Contreras, who’s 38, began his career freelancing for newspapers in Mexico, but made his reputation together with his coverage of the war in Syria. Time Lightbox showcased his work in December, 2012.

“[Contreras] has managed to light up and distill the horrors of the…war — more consistently than any of his often more-experienced peers,” Time senior photo editor Phil Bicker wrote in a narrative that accompanies the 44-image gallery. “What makes Contreras’s work in Syria much more astonishing is the truth that he has, in a feeling, pop out of nowhere to grow to be the single photographer whose work is frequently seen because the photographic record of the conflict.”

AP says it has removed all of Contreras’s images from its archives. There have been about 500 in all. AP says it has compared as many because it could to Contreras’s original image files, and located no other instances of alteration.