A Mattapan remains behind bars today following his indictment and Superior Court arraignment as a principal in the murders of four people in Mattapan late last year, Suffolk County District Attorney Daniel F. Conley said.

DWAYNE MOORE (D.O.B. 6/25/77) was formally charged today with four counts of first-degree murder for the Sept. 28 shooting deaths of Eyanna Flonory, 21, of Dorchester; her 2-year-old son, Amanihotep Smith; Simba Martin, 21, of Dorchester; and LeVaughn Washum-Garrison, 22, of Roslindale.

Moore was additionally charged with armed assault with intent to murder and aggravated assault and battery for the non-fatal shooting of a 32-year-old Dorchester man during the incident near 40 Woolson St. shortly after 1:10 that morning. That man, who remains hospitalized, was critically injured in the shooting and is paralyzed from the shoulders down, prosecutors said today.

In addition to those charges, Moore additionally faces single counts of home invasion, armed robbery, unlawful possession of a firearm as an armed career criminal, and trafficking in more than 28 grams of cocaine.

The 10-count indictment charging Moore was returned Friday after a three-month investigation in the Suffolk County Grand Jury.

“Prior to Sept. 28, this defendant, with his co-defendant KIMANI WASHINGTON, spoke about a plan to commit an armed robbery,” Assistant District Attorney Edmond Zabin, chief of Conley’s Homicide Unit, told Judge Judith Fabricant. “The plan was to rob the location of drugs and cash.”

Zabin said the target of the robbery was 23 Sutton St., where Moore had previously lived with Martin. Moore knew Washington (D.O.B. 10/17/75) from state prison, where both had served time.

With a third defendant, EDWARD WASHINGTON (D.O.B. 3/28/79) of Dorchester, they drove to Sutton Street in the early hours of Sept. 28. All three were armed with semiautomatic handguns, Zabin said.

Once in the vicinity, Moore attempted to draw Martin out of the house by calling his cell phone. While they waited, Zabin said, the surviving victim arrived unexpectedly in a motor vehicle and Martin left the house to meet him.

“Kimani Washington approached the motor vehicle with a gun and ordered the victims to the ground and to strip,” Zabin said. “The defendants moved them into 23 Sutton St.,” where the three remaining victims were present.

Once inside, Zabin said, the three defendants took a safe, a large television, and a large quantity of cocaine. Some items were placed into the surviving victim’s vehicle, which Kimani Washington then drove from the scene, Zabin said.

Moore and Edward Washington then marched the victims up to Woolson Street, Zabin said. It was there that the two men, one woman, and 2-year-old child were executed.

Moore is represented by attorney John Amabile and will return to court on Jan. 20. His co-defendants are expected to be arraigned separately later this month. Kara Hayes and Catherine Rodrigues are the DA’s assigned victim-witness advocates.