TMZ reported a female friend found the 29-year-old early this morning with blood coming out of his nose and ears.
Authorities called to the house in Chicago pronounced him dead a short time later, People Magazine reported.
Family members suspect he died of a drug overdose, TMZ said.
Kovar, described on his Twitter profile page as an “EX Reality Star, Musician, Song writer, Model, Actor, Professional Wrester, Nutritiion and Supplement Enthusiast, Personal Trainer, Security Guard,” had waged a public battle against drug addiction.
USA Today reported that Kovar entered rehab during the 2007 season of “Real World.” He also sought assistance for cocaine and ecstasy addiction on "Celebrity Rehab" in 2010.
His last tweet was posted Thursday. "Do not let what you cannot do interfere with what you can do," Kovar wrote.
Earlier in the day he posted “Fall seven times, stand up eight.”
Before finding fame on reality television, the troubled star was a bodybuilder and personal trainer, the Daily Mail reported. He was also in a band for five years.
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