A member of the Pagans Motorcycle Club accused of bringing explosives into West Virginia has died in custody.

Regional Jail Authority operations manager John L. King says 57-year-old Charles Harmon Nichols was found unresponsive in his cell at the South Central Regional Jail Saturday.

King said the man known as "Tombstone Charlie" appears to have died of natural causes.

Nichols was six-foot-two-inches, weighed 375 pounds and had several health issues.

He was one of 55 defendants from West Virginia, Kentucky, Virginia, Pennsylvania, New York, New Jersey, Delaware and Florida named in a 44-count federal indictment. The charges include two murder conspiracies, kidnapping and drug dealing.

The U.S. Marshal's Service is investigating Nichols' death.

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