Credit: Scott Garfield/NBCU Photo Bank

Dearon “Deezer D” Thompson, the actor who portrayed nurse Malik McGrath on the beloved NBC medical drama ER, has died at the age of 55.

On Friday, news broke that the actor had passed on Thursday, January 7, after being found unresponsive at his Los Angeles home. It is believed Thompson died from a heart attack, though an official cause of death has not yet been disclosed. He previously underwent open-heart surgery in 2009 to replace an aorta and fix a leaky heart valve. Thompson's brother confirmed the news with a post on Instagram, which he captioned "My Big Brother! God is with you. I will miss you."

In addition to appearing in 190 episodes of ER from 1994 until 2009 as nurse Malik McGrath — including the pilot and series finale — Thompson also appeared in movies such as Fear of a Black Hat, CB4, Bringing Down the House, and Romy and Michele's High School Reunion.

Following the news, Thompson's ER costars shared their heartfelt tributes across social media. “I lost a dear friend yesterday,” Noah Wyle wrote on Instagram. “Deezer D, known to millions of ER fans as nurse, Malik McGrath, died yesterday morning. He was one of the most creative and charismatic men I’ve ever known and his gospel of positivity pulled us both up from many a dark place. I will miss him terribly. Please say a prayer for him and hold a living thought for his family today.” The original star of the series, Julianna Margulies commented on Wyle's post, “My heart is broken… He was simply the sweetest, most fun to be around. I can’t believe it!”

Mekhi Phifer, who joined the series in 2002, also shared a tribute. “What a special spirit we have all lost!” he wrote on Instagram. “Since the first day I met him on the set of ER he absolutely made me feel at home and welcomed. My brother will forever be missed! Many condolences to his friends, fans and family.”

ER producer Neal Baer also shared his condolences on Twitter, calling Thompson "wonderful to work with."


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