Shaahid Forshee, 36, of East Orange, is charged with attempted murder, aggravated assault, unlawful possession of a weapon.
Authorities say the series of events began after 3 p.m. at the Krauszer's Convenience Store on South Valley Road in West Orange, where they say the officer observed an altercation between two men.
One of the men, Forshee, was allegedly armed with a handgun.
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The officer -- who was unarmed -- intervened, and during a struggle, police say Forshee struck the officer with the gun and fired the weapon.
The bullet grazed the officer's head, causing non-life-threatening injuries.
The officer was taken to University Hospital, where he was in stable condition.
The person with whom Forshee was arguing fled the scene.
Forshee also fled and was later arrested in Newark.
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The investigation, which is being handled by the Essex County Prosecutor's Homicide/Major Crimes Task Force, is active and ongoing.
Anyone with information is asked to contact the Essex County Prosecutor's Office tips line at 1-800-TIPS-4EC or 1-877-847-7432
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