Updated

Federal authorities reportedly were investigating Tuesday after campers in a remote part of California claimed to see a group of armed men firing off hundreds of gunshots Sunday.

Officials told the Los Angeles Times that San Bernardino County sheriff’s deputies and an FBI agent responded to Deep Creek Hot Springs in the Apple Valley after the reports of gun shots and chanting. Law enforcement sources told the paper that 17 Middle Eastern men were detained.

San Bernardino County sheriff’s spokeswoman Jodi Miller said all the men were released after authorities didn’t find any evidence of crimes or warrants against them.

Miller said one rifle was found but did not have a serial number because it was bought in parts. It was deemed to be legal in California, the paper reported. Weapons and vehicles found at the scene were registered with the Department of Justice, according to a police report.

FBI spokeswoman Laura Eimiller said authorities are working with local officials to decide whether a crime was committed.

According to a police report, campers told 911 that more than 100 shots were heard and about 5 to 7 men “wearing turbans were seen in the area shooting assault rifles, handguns and shotguns.”

“They were up all night chanting ‘Allah akbar’-type stuff,” an unidentified officer was heard saying on an audio recording reported by the Victor Valley News Group.

Authorities located the group of men walking away from a creek carrying backpacks and other items. Several handguns, a rifle and shotgun were found in the backpacks, the report said.

Sheriff’s investigators contacted several hikers around the area, but none had seen or heard any guns being fired in the vicinity.

“There was no evidence found that a crime had been committed by any of the subjects who were detained and they were released,” police said.

Click for more from the Los Angeles Times.