San Diego ? A former U.S. Border Patrol agent was sentenced Friday to five years in prison for conspiring to smuggle at least 100 illegal immigrants in his government vehicle.

Oscar Antonio Ortiz, 29, had been brought illegally into the United States when he was 3 and had never attained citizenship.

U.S. District Court Judge John A. Houston rejected prosecutors’ three-year recommended sentence in imposing the stiffer term. Ortiz, he said, abused his trusted role as a “gatekeeper” into the country.

“You violated the sacred trust of your comrades,” the judge said. “As a link in the chain, they depended on you.”

Ortiz carried out his smuggling with the help of another agent, Eric Balderas, who pleaded guilty to conspiracy charges earlier this year and is awaiting sentencing.

The agents carefully coordinated their smuggling activity, according to Assistant U.S. Atty. Alana M. Wong. While one kept watch atop a hill, the other would pick up the migrants, who had already crossed the border, she said.

The migrants would be taken to a designated area where drivers working for a human smuggling organization would pick them up. The agents earned about $300 per migrant, Wong said.

Ortiz’s case prompted a review of the backgrounds of more than 40,000 border patrol agents and customs officers. Border Patrol officials said they were unaware when he was hired in 2001 that he had been detained shortly before on suspicion of trying to smuggle two illegal immigrants into the United States in his vehicle. No charges had been filed in the case.

Ortiz, who was born in Mexico, grew up in the San Diego area and served in the U.S. Navy.

Ortiz’s mother obtained the fake birth certificate when he was 3 years old, and Ortiz grew up thinking he was a U.S. citizen until he turned 18, White said.