The assistant chief of the Plymouth Ambulance has been arrested and charged with stealing narcotics meant for trauma patients from a locked office in the ambulance company's headquarters, authorities said.

Dominic Venezia, 36, of Hemlock Drive in Norristown, was taken into custody Wednesday by Plymouth Township police after investigators planted a surveillance camera in the office. By comparing that evidence with the times his key card was used to open the office, police were able to finger Venezia as the one stealing the drugs, said Montgomery County District Attorney Risa Vetri Ferman.

Venezia was arrested while on duty as a Whitemarsh Township patrolman. When confronted with the thefts, he told investigators he had a drug problem and was immediately removed from duty and placed on leave, Ferman said. Venezia was arraigned Wednesday before District Judge Francis J. Bernhardt and released after posting $5,000 bond for a preliminary hearing next Thursday. - Bonnie L. Cook