A Brockton man was held on $150,000 cash bail today at his arraignment for allegedly acting as a getaway driver for the man whom authorities say shot three people to death on Mount Ida Road early last year, Suffolk County District Attorney Daniel F. Conley said.

NIGEL A. NICHOLS (D.O.B. 11/5/85) was indicted Jan. 12 as an accessory after the fact to the March 29, 2009, murders of 20-year-old Shacora Gaines of Brockton, 20-year-old Chantal Palmer of Brockton, and 19-year-old Anthony Peoples of Boston. Nichols’s indictment came the same day a Suffolk County grand jury indicted KERON PIERRE (D.O.B. 11/26/85), formerly of Mattapan, on three counts of first-degree murder for allegedly shooting them to death.

Assistant District Attorney Mark T. Lee, deputy chief of Conley’s Homicide Unit, told Superior Court Clerk Magistrate Gary Wilson that the victims had been part of a “get-together” that ran from the evening of March 28 through the morning of March 29 to raise money for an annual West Indian and Caribbean carnival. They arrived at the event together and were preparing to leave together in the same car, Lee said.

The man who killed them, Lee said, was also present that night and early morning.

“Mr. Nichols was identified through the grand jury as a person who came to the party with the shooter,” Lee said. “As the three deceased victims and a fourth surviving victim were leaving, they were approached by the shooter and other individuals.”

A verbal altercation erupted, Lee said, prompting the gunman to “produce a semiautomatic handgun and fire repeatedly into the car.”

Gaines, Palmer, and Peoples were mortally wounded in the barrage. A fourth victim was not struck by gunfire.

Surveillance footage shows a car matching the description of Nichols’s vehicle speeding away from the scene of the murders and almost hitting another car, Lee said. Additionally, the prosecutor said, Pierre’s girlfriend was asked in the aftermath of the murders to pick him up at Nichols’s home, which she did.

Pierre disappeared from the Boston area in the days following the murders and investigators believe he may have fled to Trinidad. Conley and Boston Police Commissioner Edward Davis continue to urge anyone with knowledge of his whereabouts to call the Boston Police CrimeStoppers tip line at 1-800-494-TIPS.

Paula Connor is the district attorney’s victim-witness advocate assigned to the case. Nichols was represented by attorney Ben Brooks and will return to court on Feb. 1.