Al-Qaida in Iraq says it shot down an American helicopter Wednesday near the western city of Ramadi.

Iraqis stand near wreckage believed to be crashed US helicopter, in Ramadi,  Thursday

The U.S. military said Thursday, that it is continuing to investigate the cause of the crash, including witness reports that it was brought down by a missile. Two Marines were killed in the crash.

Al-Qaida in Iraq, which is led by Abu Musab al-Zarqawi, also said in a separate Internet posting, that it plans to execute two Moroccan embassy employees it kidnapped last month.

Meanwhile, police in Baghdad discovered the bodies of 11 men who had been kidnapped and killed. And an American soldier was killed near Baquba, north of Baghdad.

The latest developments come as Iraq's Sunni Muslims began three days of religious celebrations Thursday, marking the end of the holy month of Ramadan. Shi'ite Muslims will begin the Eid al-Fitr holiday on Friday.