GREENSBORO, N.C. – Three suspects have been arrested in the shooting death of an off-duty Greensboro police officer Saturday afternoon, officials announced Sunday.

Jamere Justice Foster, 18, is charged with first-degree murder in the slaying of Sgt. Philip Dale Nix at a Sheetz gas station on Sandy Ridge Road in Colfax, the Greensboro Police Department said in a news release.

Z'quriah Le'Pearce Blackwell, 18, and John Walter Morrison, 28, are charged with accessory after the fact to first-degree murder, police said.

Foster and Morrison also are charged with larceny and conspiracy to commit larceny. Both were being held without bail. Blackwell was being held with bond set at $500,000.

Nix, a 23-year veteran on the force, witnessed a crime at the gas station at about 4 p.m. and was shot as he approached two suspects, officials said.

Police issued a Blue Alert across the state Saturday night in a search for the suspects, but the alert was later canceled.

Nix was supervisor of the police department’s family victims unit and had served as a criminal investigations division detective, patrol corporal and patrol sergeant.

The police department said in a social media post Sunday evening that a memorial had been set up for Nix.

Colfax is a small community west of Greensboro in Guilford County.