The incident occurred at a private office complex in Cedar Grove, Essex County Prosecutor Theodore Stephens, II said.
He was treated and released at a nearby hospital for a non-life-threatening wound, Stephens said.
Ambrose joined the Newark Police Department in 1986 and became chief in 1999. He was an undersheriff in the Essex County Sheriff's Office and was public safety director for Newark from 2016 to 2021.
Ambrose's time in Newark was not without controversy. According to multiple lawsuits against the City of Newark, Ambrose was been accused of punishing police officers who supported candidates he opposed. The city settled both lawsuits, according to Daily Beast.
The Cedar Grove Police Department is investigating the shooting.
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