LOWELL — A 20-year-old Lowell man is facing firearms charges after police say he ran from the scene of a fight downtown with a loaded 9mm gun in his hand before he was caught and arrested inside the Leo Roy Parking Garage.

Officers were sent to a report of a fight involving about 10 people in the area of Bridge and Merrimack streets about 1:50 p.m., according to police.

A witness to that incident told police that one of the people involved in the fight had a handgun and fled toward Central Street, according to police.

Officers broadcast a description of that individual, and police say a suspect was spotted a short time later on Market Street.

Police say the suspect took off when officers approached him, resulting in a brief foot pursuit in which “the suspect could be seen running with a firearm in his hand,” according to a press release issued by Capt. Timothy Crowley.

The suspect was caught inside the Roy garage at Market and Palmer streets, and identified as Franklyn Diaz, 20, of Lowell, according to police.

Crowley said officers found a loaded, high-capacity pistol on Diaz when he was arrested. State law defines a high-capacity gun as any one that holds more than 10 rounds.

Diaz was being held at the police station Tuesday afternoon and will be arraigned Wednesday in Lowell District Court.

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