The photograph, filed by Adnan Hajj, showed smoke billowing from burning buildings in a Beirut suburb on Saturday, but was immediately questioned in a post by Washington DC-based graphic artist Jeff Harrell, writing that "the clone stamp tool (was used) about 63 zillion times to paint more smoke into the sky above Beirut".
Other right-wing bloggers and a community of professional photographers pored over the image, suggesting that wrecked buildings, too, had been artificially replicated to increase the appearance of damage in the city. Reuters killed the image on Sunday morning in response to the concerns.
"Reuters has suspended a photographer until investigations are completed into changes made to a photograph showing smoke billowing from buildings following an air strike on Beirut," Reuters' PR head Moira Whittle told Journalism.co.uk on Sunday. "Reuters takes such matters extremely seriously as it is strictly against company editorial policy to alter pictures.
"As soon as the allegation came to light, the photograph, filed on Saturday 5 August, was removed from the file and a replacement, showing the same scene, was sent. The explanation for the removal was the improper use of photo-editing software."
Some of the blogs, including Charles Johnson's Little Green Footballs, which in 2004 helped force CBS News to retract a story about President Bush's war record, assembled close-ups and animated images to illustrate the manipulation.
"It's so incredibly obvious," Mr Johnson wrote. "Smoke simply does not contain repeating symmetrical patterns like this, and you can see the repetition in both plumes of smoke."
Mr Hajj's photography became a hot topic earlier last week for online observers scrutinising his images of a rescue worker retrieving the body of a child killed in Israel's heavy bombardment of Qana.
Finding the pictures were part of a series of images taken over several hours by agency photographers, critics speculated that the body may have been paraded and posed for cameras by Hezbullah associates.