Six gang members have been charged in the October 2014 deaths of a business couple in Lake Wylie, who a U.S. attorney says were killed to keep them from testifying against three members of the gang in the robbery of the couple's store.

Six members of the "United Blood Nation" are charged in the killing of Debbie and Doug London, according to court documents. They could receive the death penalty. 

Deputies say Debbie London, 61, and Doug London, 63, were found shot to death in their Tioga Road home on Oct. 23, 2014. The couple's son, Daniel London, found his parents and called 911. 

After an FBI raid of Charlotte's UBN, 12 defendants were charged in a racketeering operation conspiracy.

Six of those members, Jamell Lamon Cureton, David Lee Fudge, Randall Avery Hankins II, Malcolm Jarrel Hartley, Briana Shakeyah Johnson and Rahkeem Lee McDonald, are charged in the killing of the Londons, according to a federal indictment that was unsealed on Wednesday.

In addition, Nana Yaw Adoma, Daquan Lamar Everett, Nehemijel Maurice Houston, Ibn Rashaan Kornegay, Centrilia Shardon Leach and Ahkeem Tahja McDonald were charged in the conspiracy.

Four of the people charged in connection with the case were already in custody. Two other suspects were arrested Wednesday.

Three of the members, Cureton, Nana Yaw Adoma and Fudge, previously robbed the couple's mattress store and the members were attempting to stop the Londons from testifying, according to U.S. Attorney Jill Rose.

The defendants operated under a common set of rules known as the "31" and used a ranking system. They participate in meetings, "like any other enterprise," Rose said in a press conference on Wednesday afternoon. They "discuss punishment for those they fear may be cooperating with law enforcement," she said.

On Oct. 1, Hartley and Johnson conducted surveillance of The Mattress Warehouse of Pineville on South Boulevard in an attempt to locate the Londons and kill them, court documents state.

Documents indicate the gang members not only wanted to prevent the Londons from testifying, they wanted to retaliate against the couple for previous court appearances related to the robbery case.

Doug London tried to defend the store and his life, police said, when he shot and hit one of the suspects, later identified as Cureton. Cureton went to a local hospital and was arrested on robbery charges.

Rose said that's when the defendants began to correspond and conspire with each other to plan the murder of London, "the only eyewitness to the robbery."

On Oct. 5, the gang members conducted a meeting in Greenville, North Carolina. Two days later, the members conducted a phone meeting where they planned the killing of the Londons, court documents say. Apparently, two members failed to accomplish "that goal."

That's when someone known to the Grand Jury received a text from Fudge saying that he had "sent the hit," meaning he ordered the killing of the couple.

After several more meetings, the "hitman," Rahkeem Lee McDonald, along with Hartley, Fudge, Cureton and Hankins, "conspired to, attempted to, and did murder Douglas London and Deborah London at the Londons' residence in Clover," court documents say.

Then, the members conducted another meeting to dispose of evidence from the killings, according to court documents. The next meeting was a celebration. In a telephone meeting on Oct. 25, Hartley admitted to killing the couple, the documents say.

In a press conference, Rose said Harley possessed the same pistol that was used in the fatal shooting of the Londons.

"Hartley shot and killed Deborah and Douglas in their home," she said.

Multiple sources confirmed previously to WBTV that Hartley was a "high-ranking" member of the Bloods gang. According to North Carolina Department of Corrections online records, Hartley was convicted in 2013 for conspiracy to commit armed robbery.

Officials said the FBI helped with the homicide investigation in an effort to share information about the two crimes.

Special Agent John Strong said Wednesday that the gang threat in North Carolina is "very, very strong."

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