Reports of burning mosques, like this one from Reuters remain unconfirmed, and may have been fabricated by Sunni militants.
Also, sensationalized accounts of Sunnis being dragged from prayer and burned alive by rampaging Shiites are unconfirmed, and all appear to come from the same source, police Captain Jamil Hussein, whose entire career appears to be issuing statements about Shia violence against Sunnis. Curt at Flopping Aces has researched Hussein and found a remarkable number of atrocity stories for which he is the source.
Curt also reports that he has received an email from CENTCOM that is very skeptical of the media accounts:
We are checking with the Iraqi Government to verify that Capt. Jamil Hussein is a legitimate Iraqi Government spokesperson. We haven’t heard back yet. Unfortunately, people posing as government officials often do call the media to make statements.
From the Multi-National Force's Iraqi Freedom website:
BAGHDAD — Contrary to recent media reporting that four mosques were burned in Hurriya, an Iraqi Army patrol investigating the area found only one mosque had been burned in the neighborhood...
...An alleged attack on a fourth mosque remains unconfirmed. The patrol was also unable to confirm media reports that six Sunni civilians were allegedly dragged out of Friday prayers and burned to death. Neither Baghdad police nor Coalition forces have reports of any such incident.
This is all uncomfortably reminiscent of the Reutersgate/fauxtography scandal during the Israeli/Hezbollah war, and once again brings into question just how much Western news agencies have compromised their integrity by depending on unvetted local stringers and sources.
If these incidents were embellished, as they now seem to be, they show a frightening level of sophistication about Western media. The stories all broke toward the end of the weekly news cycle so that even if they are eventually corrected, they will have at least the weekend to sink into the American psyche.