LAREDO, TEXAS (ValleyCentral) — A U.S. citizen living in Mexico has pleaded guilty to trafficking handguns in Mexico under a new anti-gun trafficking law, federal authorities announced Thursday.

Said Isaac Hernandez, 25, admitted to one count of trafficking firearms and is “the first person believed to be convicted under the new law,” known as the Stop Illegal Trafficking Firearms Act, according to a news release from the U.S. Attorney’s Office Southern District of Texas.

The act was passed June 25 as part of the Safer Communities Act, the office said.

On July 11, law enforcement officials arrested Hernandez on U.S. Interstate 35 as he was driving south towards the port of entry in Laredo. They discovered 17 firearms hidden in his car, according to the U.S. Attorney’s Office.

“Hernandez had been the subject of an investigation related to the purchasing of a large number of firearms and transporting them to Mexico,” the news release stated.

Between Jan. 21, 2020, and July 11, Hernandez purchased a total of 231 handguns in calibers of 9mm, .380 and .22, authorities stated.

U.S. District Judge Marina Garcia Marmolejo accepted Hernandez’s plea and will set sentencing later. At that time, Hernandez faces up to 15 years in federal prison.

Hernandez will remain in custody pending that hearing, authorities stated.