Around 400 guns were stolen from a UPS facility in Memphis, Tenn., on Sunday, prompting the Bureau of Alcohol, Tobacco, Firearms and Explosives to offer a $5,000 reward for details that could facilitate an arrest and conviction of the two suspects who stole the firearms.

The two suspects, who drove a U-Haul truck, are the subject of a case that is one of the largest gun thefts the agency has examined, ATF spokesperson Michael Knight said. The theft has caused concern among authorities who fear the weapons will harm public safety in Memphis and other areas.

"We are concerned that the firearms will end up on the streets not only potentially in the Memphis area, but also across the country," Knight said, per the Associated Press. "The criminal element knows no geographical boundary."

Agents from ATF and the Memphis Police Department working to figure out where the guns were shipped and their intended destination.

"It's a very tedious process that we're looking at to make sure that every firearm is accounted for, from the shipper as well as from the receiver," Knight said.

The agency is requesting the public to share social media posts, photos, and other information concerning the case.