BOSTON -- A third New York man has been indicted in connection with the shooting death of Justin Cosby, 21, of Cambridge.

Jason Aquino, 23, of Manhattan, N.Y., was indicted by a Middlesex grand jury on charges of accessory after the fact of armed robbery and carrying a firearm without a license, said Middlesex District Attorney Gerry Leone.

According to authorities, on May 18, at approximately 4:48 p.m., Harvard University Police responded to the Kirkland House, located on Dunster Street in Cambridge for reports of shots fired. Cambridge Police were also notified and responded to the scene.

Cosby was found at the scene, suffering from an apparent gunshot wound to the abdomen. He had left the Kirkland House and ran to the intersection of Dunster Street and Mount Auburn Street, where he collapsed.

Cosby was transported to Beth Israel Hospital and was pronounced dead the following morning. Cambridge Police and Harvard University Police, with the assistance of the Massachusetts State Police and the Middlesex District Attorney's Office, began an investigation into the circumstances of the shooting.

Based on the investigation, it was determined that Jabrai Jordan Copney, Blayn Jiggetts and Aquino, none of whom were students at Harvard University, arranged for a meeting with Cosby planning to rob him, said Leone.

During the meeting with Cosby in a common area inside the Kirkland House multiple shots were fired, Leone said. One of those shots struck Cosby, resulting in his death.

Copney, Jiggetts and Aquino fled the scene and returned to New York City that evening on a bus from Boston, said Leone.

Copney, 20, of New York, was arrested in connection with the murder on May 21 and charged with murder, accessory after the fact to murder, and possession of a firearm, Leone said. He was ordered held without bail.

A Middlesex Superior Court grand jury later indicted Copney on charges of first-degree murder, accessory after the fact of murder, attempt to commit a crime, armed robbery and possession of a firearm.

Jiggetts was arrested June 9 in Harlem by Massachusetts State Police, Cambridge Police and detectives from the New York City Police Department Manhattan North Homicide Unit, said Leone.

He appeared in Manhattan Criminal Court on July 10, and was charged as a fugitive from justice. He was ordered held without bail.

A Middlesex grand jury indicted Jiggetts on charges of first-degree murder, accessory after the fact of murder, armed robbery, and possession of a firearm on July 10, said Leone. He has not been arraigned in Massachusetts yet because the defendant has not been extradited from New York.

Aquino was arrested on July 30 in Manhattan, also on a Massachusetts warrant by Massachusetts State Police, Cambridge Police and the New York City Police Department, said Leone.

He was arraigned in Manhattan Criminal Court on July 31, at which point he waived extradition.

Aquino was arraigned in Cambridge District Court on August 3 and ordered held without bail. He faces charges of first-degree murder, accessory after the fact of murder, armed robbery and possession of a firearm, Leone said.

Harvard University Police, Cambridge Police, state police, and the Middlesex District Attorney's Office continue to investigate Cosby's murder.