Reg E. Cathey, the Emmy award-winning actor best known for his role on House of Cards, has died at age 59.

The tragic news was announced Friday by Hollywood producer/writer David Simon, Cathey’s good friend and former colleague.

“Reg Cathey, 1958-2018. Not only a fine, masterful actor—but simply one of the most delightful human beings with whom I ever shared some long days on set,” he wrote on Twitter. “On wit alone, he could double any man over and leave him thinking. Reg, your memory is a great blessing.”

Cathey worked with Simon on a number of projects, including the miniseries The Corner as well as HBO’s The Wire. He also landed acting credits in shows like ER, Law & Order, 30 Rock, The Good Wife, and Inside Amy Schumer. His role Freddy Hayes in the Netflix series House of Cards, however, was his most notable performance, as it earned him a 2015 Emmy award for Outstanding Guest Actor in a Drama Series. The Yale alumnus was also nominated for the same role, in the same category in 2014 and 2016.

Though the details surrounding Cathey’s death have not been revealed, sources told TMZ he had been battling lung cancer. 

Industry figures, including actors Miles Teller and House of Cards creator Beau Willimon, shared their memories and condolences on Twitter: