Two Mexican nationals were arrested in Colorado after deputies discovered 180,000 rounds of ammunition in their van during a routine traffic stop.

According to a news release from the U.S. Attorney’s Office for the District of Colorado, the suspects were identified as Caesar Ramon Martinez Solis, 41, and Humberto Ivan Amador Gavira, 24.

On March 26, the Fremont County Sheriff’s deputies stopped the van occupied by the suspects in Cañon City for failing to dim its headlights and not using a turn signal. 

After the driver, Martinez Solis, gave permission to search the van, deputies found 180 boxes of ammunition, about 150 boxes of .308 rounds and 30 boxes of 7.62 rounds. Each box was marked as containing 1,000 rounds.

Neither man had a permit to possess or transport ammunition in the U.S., and their visas did not allow them to buy or move firearms or ammunition. They also lacked a hazardous materials permit and insurance for the van.

The men told investigators they had entered the U.S. the day before the stop. According to a federal affidavit, they traveled to Denver, bought the van, then drove to Salt Lake City, Utah, to purchase the ammunition at a gun store. They said the ammunition was meant for delivery in Pueblo, Colorado.

On Wednesday, the U.S. Attorney’s Office for the District of Colorado charged both men with Unlawful Possession of Ammunition by Alien Admitted Under a Nonimmigrant Visa.

The suspects are now in the custody of the U.S. Immigration and Customs Enforcement.