Nelsan Ellis died earlier this month from what his family claims was complications from alcohol withdrawal, and now a pal close to the late star exclusively claims to RadarOnline.com that the actor had secret ties to the Church of Scientology and a “dangerous detox program” through the bizarre religion.

The True Blood star – who played flamboyant Lafayette Reynolds – was hugely popular with fans and fellow cast members of the HBO vampire show. And according to a former pal, he was a closet Scientologist who secretly attended cult-like group’s dangerous detox program.

Steven Mango, an ex-Scientology poster boy who claimed to have acted as Nelsan’s “twin” in the group’s Purification Rundown — or “Purif” for short — told RadarOnline.com he believes the program could have caused, or contributed to, Nelsan’s death July 8 at the age of 39. “I almost died on the program,” said Mango.

Mango claims the program consists of ingesting massive “vitamin bombs,” running on a treadmill and sitting in a sauna for four to five hours daily.

As previously reported by Radar, Nelsan’s father said his son’s kidneys failed, he had a blood infection, his blood pressure dropped and “his dear sweet heart raced out of control.” Meanwhile, his manager, Emily Gerson Saines, attributed the death to the actor’s solo attempt to quit drinking.

Mango, who “escaped” the bizarre religion in 2012, told Radar he met Nelsan earlier that year outside the purification area Scientology houses in the basement of its Celebrity Center. The area contains two saunas, he said. “There was 10 to 15 people in the program in the evening,” Mango revealed. “I was sitting in the sauna and Nelsan was in the corner reading a script. You take five to 10-minute breaks, where you step out of the sauna into a sitting area. My friend came up to me excitedly to tell me that the new guy was Lafayette from the HBO show True Blood.”

“He was down to earth,” Mango added. “Nelsan later became my twin in Scientology. A twin is your partner who you do the program with. You oversee the other person while on the program and you sit with them in the sauna, fill out worksheets together.”

Mango is not aware if Nelsan continued in Scientology — or the Purif program — after he quit the group in 2012 and claims that it branded him a “suppressive person,” an official enemy. Scientology also denied any involvement in Nelsan’s death.

He claims that Nelsan had remained silent about Scientology out of fear the group’s anti-gay positions would sour his career.

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