Byron Thomas, 35, of Paulsboro, was arrested over the weekend and charged with murder.
According to court documents, Thomas - along with three other men - shot and killed Detective Sergeant Monica Mosley during a home invasion in Bridgeton.
Those suspects were earlier identified as Jared Brown, 31, of Bridgeton; Nyshawn Mutcherson, 29, of Vineland; and Richard Willis, 32, of Gloucester City.
A fifth suspect, 38-year-old Cyndia Pimentel of Paulsboro, is charged with tampering with evidence.
The murder happened back on October 15 on the 600 block of Buckshutem Road in Bridgeton.
According to court documents obtained by Action News, the suspects broke into Mosley's home around 10:30 p.m. and shot her.
Before the detective died from her injuries, authorities say she was able to shoot Mutcherson, who later showed up at Inspira Medical Center.
The motive for the killing has not been revealed.
Mosley was a mother to two daughters and also a grandmother.