Four people have been arrested in connection with the shooting death of an off-duty Los Angeles police officer earlier this week.

Los Angeles County Sheriff’s Department officials however, did not release any further information about what the people were arrested on suspicion of, and they have not been identified, KTLA reports.

Officer Fernando Arroyos, 27, was murdered during a robbery attempt while he and his girlfriend were shopping for a home in South Los Angeles Monday night.

At one point, the officer told his girlfriend to run away. Authorities believe an argument transpired and Arroyos exchanged gunfire with at least one of the suspects.

Jose Reyes, the officer’s stepfather, believes his stepson was targeted over a gold chain worth about $200 that he was wearing at the time.