MINNEAPOLIS (WCCO) — Ten people have been accused of bribing and intimidating witnesses to recant their testimony in a Minneapolis murder trial that sent three men to prison for life, Hennepin County Attorney Mike Freeman announced Monday.

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The charges are the results of a 10-month investigation by Minneapolis police and the Minnesota Department of Corrections.

Freeman says the main defendant is Lamonte Rydell Martin, 24, is charged with 12 counts of bribery, tampering with a witness and accomplice after the fact. Martin is allegedly the mastermind in an operation to get several witnesses to sign affidavits, claiming they testified against Martin, Cornelius Jackson and Jonard McDonald for gunning down Christopher Lynch in north Minneapolis in 2006.

Martin’s mother, Heidi Marie Mastin, 47, was arrested over the weekend and will be charged with accomplice after the fact and bribery. She allegedly helped funnel money into the prison account of one of the targeted witnesses.

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Girlfriends of some of the men were used to wire money to the witnesses’ prison accounts or to set up three-way telephone calls between Martin and others to plan their actions, the complaint said.

“It’s outrageous enough that they committed the murder and other crimes in the first place,” said Freeman. “Now they are using a mother, their girlfriends and other gang members in prisons around the state to bribe and intimidate the men who testified against them. Congratulations to investigators on an excellent investigation. We are going to come down hard on these defendants for trying to corrupt the system and for threatening innocent family members.”

Martin, a member of the 1 9 Dipset gang, had an earlier appeal denied by the Minnesota supreme court in October 2009. He needed the recantations as new evidence for his current appeal.

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Besides bribery, one of the imprisoned witnesses told investigators he was afraid he’d be killed by a 1 9 Dipset gang member in prison. In one fight, his neck was cut, he told investigators. Another witness reported being attacked every day until he put his name on the affidavit.