A Mexican man has been sentenced to 30 years in federal prison in the 2010 killing of a U.S Border Patrol agent that revealed the botched gun-smuggling investigation known as Operation Fast and Furious.

Manuel Osorio-Arellanes was sentenced Monday after pleading guilty in Brian Terry's shooting death.

The gunfight erupted as Manuel Osorio-Arellanes and four other Mexican men who are accused of sneaking into the country to rob marijuana smugglers approached Terry and three other agents.

Two rifles bought by a gun-smuggling ring being monitored in the Fast and Furious investigation were found at the firefight's aftermath.

Authorities who conducted Fast and Furious have faced criticism for letting suspected gun buyers for a smuggling ring walk away from Arizona shops with weapons, rather than arresting them and seizing the guns.