LAS VEGAS (AP) — Police in the Las Vegas suburb of Henderson say they're investigating a report that a truck and trailer containing about 400 firearms was stolen from a casino parking lot.

Henderson Police Officer Rod Peña said Thursday that police could only release few details about theft because it could jeopardize the safety of officers in the ongoing investigation. Peña said he expected to have more updates later Thursday.

He said the trailer was reported stolen at the Fiesta Henderson hotel-casino around noon Tuesday but that he couldn't explain who owned the trailer, why it was full of guns and whether police have any suspects.

Peña says police are working with the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives.

Messages seeking comment from the ATF were not immediately returned.