BOSTON -- A Boston firefighter faced charges Monday after he was accused of doing drugs while on duty.

Anthony "Tony" Gaston, 47, an inspector with the department's Fire Prevention Division, was found Friday afternoon with marijuana inside his fire vehicle while on duty on Dunlap Street, according to police.

Video: Firefighter Faces Charges

Officials said that he was in uniform doing investigations for the department at the time of his arrest.

Gaston pleaded not guilty to two counts of drug possession charges. His bail was revoked during his arraignment Monday in Dorchester District Court.

Officials said that police were on routine patrol when they spotted Gaston in his vehicle with two other men smoking marijuana. Inside Gaston's vehicle, police said that officers found several bags of marijuana, Percocet and large amounts of cash.

Gaston, a 26-year veteran of the department, was placed on administrative leave and will be asked to submit to a drug test.

The city of Boston is in the process of negotiating a new contract with firefighters, and the issue of mandatory drug testing has been a sticking point. Currently, mandatory drug testing is not required for members of the fire department.

In August, Boston firefighters Paul Cahill and Warren Payne were killed in a West Roxbury restaurant fire. News reports on the autopsies said that at the time of the fire, Payne had traces of cocaine in his system, and Cahill had a blood alcohol level three times the legal limit.

A report released last month by the fire department's board of inquiry concluded that drugs and alcohol were not factors in their deaths.