An alleged Morse Street gang member arrested on federal drug charges on Friday was charged Monday with murdering Tyler Lawrence, 13, of Norwood at Babson and Fremont streets in Mattapan on Jan. 29, the Suffolk County District Attorney's office reports.

Csean Alexander Skerritt, 34, was charged with murder and various firearm and ammunition charges, as well as being a Level 3 armed career criminal, the DA's office reports. In 2017, he was found not guilty of first-degree murder for a 2014 shooting death on Dorchester Avenue in Dorchester's Ashmont neighborhood.

Skerritt was arrested Friday by federal agents on a charge of distributing 40 or more grams of fentanyl after he allegedly sold the drugs to a "cooperative witness" working with the FBI. Even as local authorities were charging him with the boy's murder Monday, he was appearing in US District Court in Boston to face that charge.

According to an affidavit by an FBI agent on the case, Skerritt, also known as Shizz Grimmy, sold 55 grams of the drug for $1,500 to the informant on Feb. 1 - three days after he allegedly gunned down the boy.

Skerritt originally planned to use his mother's house as the place to conduct the sale, but later changed to another location a couple blocks away. The affidavit does not say where in Boston this was.

Skerritt, familiar to FBI agents and BPD officers for his other past crimes, got into a gray Altima with California plates and drove to the new location to make the sale, the affdavit reports.

At his initial appearance in federal court Monday, a magistrate judge ordered him held in federal custody until at least a probable cause hearing on Feb. 14.

In 2010, Skerritt was arrested on gun charges on Olney Street, for which he was later convicted.