Updated

McALLEN, Texas -- Two Mexican nationals caught in Texas with 147 assault rifles, 10,000 rounds of ammunition, high-capacity magazines and bayonets have started serving short federal sentences after pleading guilty to entering the U.S. illegally.

Federal prosecutors released the names of Damaso Alberto Rueda Cabrera and Arnulfo de la Cruz Sanchez on Thursday along with the unusual announcement that the men made their initial appearances in federal court, pleaded guilty and were sentenced to terms of 10 days and 45 days, respectively, all on Tuesday.

In a prepared statement, U.S. Attorney Jose Angel Moreno said the investigation continued and no further comment would be made by any of the agencies involved. U.S. District Magistrate Judge J. Scott Hacker sentenced both men. Marissa Perez-Garcia, head of the federal public defenders office in Laredo, said she had no comment on the case.

Laredo police pulled over the two men Saturday afternoon. Police said it was the biggest weapons seizure in the area in years and that while the investigation was ongoing, it appeared clear the guns were destined for Mexico.

De la Cruz, 53, of Nuevo Laredo, Mexico, waded across the Rio Grande into Laredo on May 28, according to court records.

Rueda, 20, of Reynosa, Mexico, was the driver and had been in the U.S. since illegally crossing the border Dec. 15, 2008, according to court records.

The Bureau of Alcohol, Tobacco, Firearms and Explosives and Immigration and Customs Enforcement are conducting the investigation. The men remain in federal custody.

The seizure came just two weeks after Mexican President Felipe Calderon suggested in a speech to a joint session of Congress that the U.S. consider reinstating the assault weapons ban. Mexico has long argued that easily obtained weapons in the U.S. had escalated Mexico's violent drug war.

More than 23,000 people have died in drug-related violence in Mexico since Calderon declared war on drug traffickers after taking office in December 2006.