His death, in New York City, was announced on his website.
According to The Hollywood Reporter, he died on Tuesday, May 27 at Mount Sinai Hospital in Manhattan from an illness after being diagnosed with cancer in February.
He was best known for his role as boxer Jack Dempsey on HBO's Boardwalk Empire. He also appeared on Netflix's Daredevil, Orange is the New Black, and Manifest, Fox's Gotham, as well as CBS's FBI and Blue Bloods, and Elementary.
Raised in western Texas, Harjes studied acting in college, before performing in Dallas–Fort Worth area theatrical productions. He then moved to New York City.
Harjes, a student of martial arts, is survived by his parents, sister, nephews, and nieces, and his former wife.
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