BAGHDAD, Iraq – A U.S. ammunition dump on the southeastern edge of Baghdad caught fire late Tuesday, setting off at least a half-dozen thunderous explosions and several smaller ones that rattled windows across the city.

Despite the size of the blasts, no casualties were reported, Spc. Jennifer Fulk, a U.S. military spokeswoman, said early Wednesday. There was no information yet on the cause of the fire, Fulk said.

An insurgent group called Al Fataheen Army took credit for the damage in a posting on an Islamic forum used by various insurgent groups in Iraq.

The group said it had attacked the base with several missiles at 11:55 p.m., but that timing cast suspicion on the claim. The explosions, which could be felt throughout the city, had begun about an hour earlier.

The same group claimed responsibility for attacking U.S. camps in northern Iraq on Sunday.

The blasts were the culmination of a particularly violent day in Baghdad.

Police reported that at least five bombs exploded throughout the city, killing at least 10 civilians and at least one police officer. Police also said they’d discovered at least 60 bodies in the 24 hours that ended at 6 a.m. Tuesday. The bodies were bound hand and foot and showed signs of torture, the police said.

An unknown number of troops from the 4th Infantry Division based at Fort Hood, Texas, were at Forward Operating Base Falcon when the base’s ammo dump began to explode.

A military statement said the fire began at about 10:40 p.m. and ignited tank and artillery shells and small arms ammunition. The fire, clouds of smoke and flashes from the ammunition detonating could be seen for miles.

The fire was contained on the base by emergency first responders, and the damage wasn’t expected to hinder military operations, the statement said.