A Portland police officer charged with domestic assault and firing a gun during the incident pleaded not guilty today in Cumberland County Superior Court.

Brian Regan, 39, of Westbrook, is charged with reckless conduct with a dangerous weapon and criminal threatening with a firearm, both felonies, and domestic violence assault, criminal threatening and two counts of assault, all misdemeanors.

Westbrook police arrested Regan at his house March 18 after his wife Heidi Regan reported the alleged incident to Portland police.

Regan maintains that his wife attacked him and he acted in self-defense.

Regan’s bail was kept at $500 cash. Attorneys for the state and for Regan have 45 days to file court motions.

Regan is a 14-year veteran of the department. He was indicted in 2002 on charges that he assaulted a drug suspect after a high-speed car chase through Portland. He was acquitted of the charges, but suspended for six months after an internal affairs review showed he had used excessive force.

Regan was placed on administrative leave with pay after his arrest in March.