A gang leader once described as one of the city's most dangerous criminals was convicted of three murders and drug and gun charges Tuesday in a vast federal racketeering case stretching back to the mid-1990s.

A jury found Telly Hankton, who is already serving a life sentence for a state murder conviction, guilty along with three co-defendants, including two of his cousins.

All four face possible life sentences. Federal authorities said last year that they would not seek the death penalty in the case. Sentencing was set for Nov. 9.

The scene in U.S. District Judge Martin Feldman's courtroom was mostly calm as the verdict was read, although Walter Porter, who was convicted in three killings, could be heard complaining.

"It's a railroad," Porter said at one point.

Hankton's cousins Andre Hankton and Kevin Jackson were each found guilty of at least one death in the case.

There were once 13 defendants, but that number dwindled amid plea deals that included Telly Hankton's mother, Shirley Hankton, who pleaded guilty in May to racketeering.

New Orleans police previously described Telly Hankton as one of the city's most dangerous criminals. After Curtis Matthews, the brother of a witness in a case against Hankton, was shot and killed in 2011, Mayor Mitch Landrieu held a news conference with law enforcement officials in front of the daiquiri shop where the shooting occurred.

"We're coming to get you," he declared.

Porter was convicted Tuesday for Matthews's death. He also was convicted of assault in the shooting of Curtis Matthews' brother, John Matthews, now 70, who testified against Hankton.

Hankton, 40, was convicted in state court for killing Darnell Stewart in 2008. He was convicted in the federal trial for the deaths of Stewart and two other men.