GREENFIELD — Brian R. Mentz, 49, of Jacksonville, Vt., has been arraigned in Greenfield District Court on charges of unlawful possession of a large capacity firearm, unlawful possession of ammunition and unlicensed operation of a motor vehicle.

According to a report by Officer Adam Paicos of the Erving Police Department, Paicos was patrolling with Officer Nemours Duteau in the area of the French King Bridge last Tuesday about 10 p.m. when he observed a vehicle parked at the rest area beside the bridge.

Paicos reported that the area is routinely checked for suspicious activity as an attractive landmark for suicide attempts and criminal activity, and it is unusual to see a vehicle there so late at night.

As he drew closer, Paicos reported, he saw Mentz leaned back in the driver’s seat sleeping. Once he had roused Mentz and established he was alright, Paicos noticed a slight odor of liquor coming from the vehicle.

Upon scanning Mentz’s license, Paicos found it was both suspended and expired, and placed Mentz under arrest.

When Mentz was searched, he told Paicos he had no firearms, according to the report. However, he then asked to take his wallet, his cell phone and his wife’s gun. Paicos informed Mentz that he illegally possessed a firearm without a license in the state of Massachusetts.

The gun, a 9mm Glock 19, was found in a black carrying container under the passenger seat. The gun was loaded with one round in the chamber and 14 additional rounds. The pistol case contained two additional magazines with 15 rounds each.

“The storage of the firearm indicates to me that it was intentionally concealed in the motor vehicle in order to avoid detection from law enforcement,” Paicos wrote in his report, adding that the pistol case was also hidden under a briefcase.

A search of Mentz’s criminal history in Vermont came back clean.

Police also found 16.6 grams of marijuana in a plastic, vacuum-sealed baggie within a brown paper bag, which was seized. A civil disposition violation was issued for possession of under one ounce of marijuana.

Mentz was arraigned in court Wednesday under Judge Paul Smyth. He was released under the special condition that he not possess a firearm in Massachusetts without a valid license to carry, and advised of the potential for bail revocation. A pretrial conference was scheduled for Aug. 10.