Police in the southern-Arizona town of Sierra Vista have arrested a Border Patrol agent on suspicion of sexual conduct with a minor. 

A lengthy investigation conducted by both Sierra Vista Police and the Department of Homeland Security led to a grand jury indictment of 49-year-old Dana Thornhill, who eventually barricaded himself in a church, says Sierra Vista police Lt. Sean Brownson.

"When somebody is accused of what we consider heinous crimes such as this, we feel very vigilant to make sure that justice is served," Brownson said. "We would feel that way regardless of what his profession was, regardless of whether he’s law enforcement or not."

Thornhill was taken into custody after a four-hour standoff and is being held in the Cochise County jail without bond.