A 17-year-old District youth charged in the fatal shooting of another teen at the Deanwood Metro station in March is also a suspect in an unrelated killing that occurred late last year, according to court documents.

The new allegations against Maurice Bellamy are laid out in charging documents for a man who was arrested Tuesday in the slaying of Arthur Baldwin Jr., a Secret Service officer who was shot waiting for a friend. Bellamy is not charged in Baldwin’s killing, but the documents state that he and the other man shot Baldwin during a Dec. 15 robbery in Southwest Washington.

Bellamy has been held in the D.C. jail since his arrest in the March 25 fatal shooting of 15-year-old Davonte Washington. Authorities said Washington, who was on his way to get a haircut for Easter, was targeted simply because he or a sibling looked at the shooter the wrong way.

Bellamy, who was charged as an adult with second-degree murder in Washington’s death, is scheduled to appear Friday in D.C. Superior Court. Calls to Bellamy’s D.C. public defender were not returned Tuesday.

[Suspect charged in fatal shooting of 15-year-old at Deanwood Metro]

Court documents filed in connection with the Metro shooting say that Bellamy lived in a group home in Northwest Washington and grew up in Prince George’s County. Police said they traced him to a Facebook page with pictures of him labeled, “SHOOTA­ MOE, AKA MOE CITY.”

Washington’s killing sparked outrage in the city, with authorities saying there was no motive, apart from a glance. The victim and alleged shooter did not know each other, police said.

Just months before Washington was killed, officers found Baldwin lying in the 4700 block of First Street SW, according to court papers. He had been shot five times.

[Secret Service officer on leave in domestic incident fatally shot]

One witness told police that the victim was in a car when three men approached and opened the doors and trunk, according to court papers. Shots were fired, and the man in the car ran and collapsed.

Other witnesses identified the shooters as Bellamy and Charles Sims, 29, who has been charged with murder. According to the court papers, a witness told police that Bellamy shot first, as Baldwin tried to wrestle his gun away. Sims then fired. Baldwin’s iPad and wallet were taken, but there was no cash in the wallet.

At the time of his death, Baldwin, 30, had been suspended from the Secret Service after a domestic incident with his former girlfriend.

Ming Cardwell, one of Baldwin’s sisters, said the arrest is “like a weight lifted because we didn’t want these people to walk free to hurt someone else.”