Federal law enforcement officers were on their way to Denton Tuesday afternoon to take two county prisoners into federal custody after officers found thousands of rounds of ammunition, more than a dozen assault rifles and several other weapons, ski masks and body armor in the truck they were driving on Interstate 35W near FM407.

The cache apparently was on its way to be smuggled into Mexico, according to court records. The serial numbers had been obliterated on most of the weapons, authorities said.

Since the weapons were not manufactured in the United States and the suspects had to have obtained them through interstate commerce, it constitutes a federal offense, according to the affidavit.

Agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives planned to add char­ges of possession of weapons with obliterated serial numbers and conspiracy to possess weapons with obliterated serial numbers to the state charges filed last Thursday, said ATF spokesman Tom Crowley.

Victor Manuel Villalpando, 29, of Burleson was in Denton County Jail on state charges of possession of a prohibited weapon (short-barrel firearm), unlawfully carrying a weapon, evading arrest and tampering with identification numbers on personal property. Noberto Estrada, 24, of Fort Worth was in county jail on state charges of possession of a prohibited weapon, unlawfully carrying a weapon, and tampering with identification numbers on personal property.

The case began Thursday about 6:25 p.m. as Texas Department of Public Safety Trooper David Farrell was patrolling on Interstate 35W northbound.

He saw a GMC Yukon also traveling north near the intersection with FM407. The Yukon was traveling with no front license plate, which is required by Texas law.

According to court records, Farrell stopped the Yukon and checked with the driver, Villalpando, who did not have a valid driver’s license. Both men seemed unduly nervous, the trooper noted.

The trooper received permission to look inside the Yukon, but when he began searching, Villalpando fled on foot. The trooper detained Estrada and called for help in searching for Villalpando.

With the help of a helicopter and officers from several Denton County law enforcement agencies, Villalpando later was found hiding in the area in a muddy creek bed.

The Yukon was towed to the Denton County Sheriff’s Office, where county forensic investigators processed it. Sheriff’s Capt. Jeff Wawro said the forensic deputies were processing about 11,000 rounds of ammunition found in the truck, numerous long guns and three handguns.

About half the weapons are AK-47 rifles. The officers also found 20 ski masks and some body armor.

“This was a really good job by the trooper,” Wawro said. “DPS took a lot of weapons and ammunition off the streets.”

The two men were part of an active investigation into the illegal transportation of firearms from the United States to Mexico, according to the affidavits.

According to information from the ATF, the agency is targeting weapons smuggling to Mexico in an operation called Project Gunrunner. Gun smugglers are illegally transporting thousands of weapons — assault rifles and large-caliber handguns — into Mexico to aid drug smuggling and trafficking, and hundreds of innocent people and law enforcement officers are being killed with them, according to the ATF Web site.

DONNA FIELDER can be reached at 940-566-6885. Her e-mail address is dfielder@dentonrc.com .