The man who founded a violent gang in Portsmouth that eventually spread its influence into parts of Suffolk and Chesapeake was sentenced Thursday in federal court to a term of life plus 10 years for gang-related crimes.

James Alexander Mack, 25, also known as “OG Mack,” founded the Bounty Hunter Bloods in the Cradock area of Portsmouth and was instrumental in the gang’s cooperative arrangement with another street gang, the Nine Tech Gangsters, according to court documents.

The organization operated brazenly in various neighborhoods in Portsmouth, Chesapeake and Suffolk for several years, until local, state and federal investigators combined their efforts and resources and sought federal and state indictments against Mack and other members of both gangs.

“James Mack founded a violent gang that terrorized neighborhoods in Portsmouth, Suffolk, and Chesapeake,” said U.S. Attorney Neil H. MacBride. “Residents can feel safer knowing that law enforcement is committed to putting gangsters like Mack behind bars for the rest of their lives.”

Mack pled guilty in June to one RICO count and one count of possessing a firearm during a crime of violence. The RICO count includes various acts of racketeering that Mack participated in as a gang member — attempted murder, robberies and conspiracy to distribute controlled substances, among others.

Court documents portray Mack as the man at the head of an extremely violent group of criminals that displayed little fear of apprehension or sympathy for its victims.

In a 2006 robbery, Mack and a fellow gang member robbed a man sitting in his car with a woman in Portsmouth’s Cavalier Manor. They made the victim take off his pants and then forced him into his home, where they robbed him of money and jewelry.

In February 2007, he and fellow gang members robbed the owner of a Portsmouth convenience store, followed the owner home and then shot him in the hip and the leg when he attempted to run. During a home-invasion robbery that April, they robbed the victims at gunpoint with a 2-year-old baby present in the home. Later the same month, they pistol-whipped two victims during another home invasion, and one of the victims dove out a window to avoid being shot.

According to prosecutors, Mack also was heavily involved in distributing drugs in both Portsmouth and Suffolk.

Mack was arrested in April during a sweep that resulted from an investigation that involved the FBI, the Suffolk and Portsmouth police departments and the Virginia State Police. A total of eight members of the two gangs were arrested during that sweep, including two with Suffolk addresses.

Danyell Jamar White, 21, and Cameron Mychal Evans, 21, both of Suffolk, were among eight suspects “charged with terrorizing neighborhoods in Portsmouth, Suffolk and Chesapeake,” U.S. Attorney Neil H. MacBride stated in an announcement of the indictments in April.

White pleaded guilty in May to racketeering and firearms charges and was sentenced in August to a total of 20 years in a federal prison. Evans pleaded guilty in May to one count of assault with a dangerous weapon in aid of a racketeering activity and one count of possession of a firearm in furtherance of a crime of violence.