Three men have been sentenced to life in prison for operating a murderous Southeast Washington drug gang that prosecutors said stopped at nothing to protect its turf, even if that meant killing witnesses.

The three were convicted in April of numerous racketeering, murder, drug and firearms charges after a lengthy trial before U.S. District Judge Rosemary M. Collyer of the District’s federal court.

On Friday, Collyer sentenced the gang’s ringleader, Mark Pray, 31, to a prison term of life plus 130 years. Later in the day, the judge sentenced Kenneth Benbow, 32, to life plus 35 years in prison for his role in the conspiracy. Collyer sentenced Pray’s “enforcer,” Alonzo Marlow, 32, to a term of life plus 55 years Thursday.

“The defendants inflicted a massive amount of harm and we are deeply satisfied by these convictions and sentences,” Assistant U.S. Attorney Anthony Scarpelli, who helped prosecute the case, said after the final sentencing.

Pray ran his organization out of the Barry Farm neighborhood in Southeast Washington and was convicted of participating in at least three killings. He and Benbow ambushed and fatally shot Van Johnson Jr., 28, in Prince George’s County in 2008 because they felt Johnson had been speaking ill of Benbow.

In January 2010, Pray consulted with Marlow before his enforcer killed Jheryl Hodge, the 20-year-old younger brother of a rival dealer. Months later, Pray directed Marlow to execute 44-year-old Crystal Washington, a mother of four.

Washington was slain just days before she was slated to be a government witness against Pray and three others in a drug trial. Marlow was wearing a GPS ankle bracelet that tracked his movements to within a few feet of Washington and Hodge when they were killed, according to trial testimony.

The FBI, Park Police, D.C. police and Prince George’s County police began an intense investigation of Pray’s gang shortly after Washington was slain.

“Each of these murders alone justify a life sentence for their cold-blooded nature,” read court papers filed by Scarpelli and Assistant U.S. Attorney Matthew P. Cohen.

The sentences come a month after a Maryland man was sentenced by a federal judge in the District to life in prison for killing a government witness in an unrelated case.

That man, Weldon Gordon, 34, was convicted in February of fatally shooting 32-year-old Andre Hayes in 2008. Hayes had been cooperating with federal agents in an investigation of drug activities and twice purchased crack cocaine from Gordon.

A spokesman for U.S. Attorney Ronald C. Machen said Friday that prosecuting those who hurt or kill witnesses was an office priority.

“Striking out against witnesses is no way to escape justice,” Machen said in a statement after Gordon’s sentencing.