A Bronx police officer was taken into custody Friday and charged with armed robbery, conspiracy and drug trafficking, authorities say.

According to federal prosecutors, transit officer Jorge Arbaje Diaz was part of a crew that has been kidnapping and torturing drug traffickers to extort narcotics and money since 2003.

Prosecutors say Diaz and two of his accomplices are responsible for more than 100 armed robberies along the East Coast that brought in millions of dollars in drug proceeds. They claim that on at least one occasion Diaz, who has been on the force for the past three years, was on duty while committing a robbery.

During a press conference Friday, Police Commissioner Ray Kelly said he was disappointed to hear about the officer?s alleged involvement in criminal activities.

Diaz pled not guilty to all charges against him; his attorney refused to comment on the case. The officer is expected back in court Dec. 15. He is facing life behind bars if convicted.