U2's Tour Manager Dennis Sheehan Found Dead in L.A. Hotel Room

U2's longtime tour manager Dennis Sheehan was found dead Wednesday morning in his Los Angeles hotel room.

The Los Angeles County Fire Department tells ET that they responded to a cardiac arrest call at 5:34 a.m. at the Sunset Marquis Hotel. According to the coroner's office, they are looking at this as a "probable natural cause death" unless the investigation uncovers anything different. The coroner's office added that, depending on the history of the deceased and the circumstances, an autopsy may not need to be performed, but that is undecided at this time as it is still an open investigation.

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"We've lost a family member, we're still taking it in," U2 frontman Bono said in a statement posted on the group's website. "He wasn't jut a legend in the music business, he was a legend in our band. He is irreplaceable."

Sheehan did a rare interview in 2013 and revealed that he got his first job as a tour manager at the age of 19. Over the years, he worked with the likes of Led Zeppelin, Iggy Pop, Patti Smith and the late Lou Reed. "They were about to bring out The War album," recalled Sheehan of first starting with U2 in 1982. "And we haven't looked back since."

U2 kicked off their week-long concert series in L.A. on Tuesday at The Forum, but it's unknown if they will be canceling their next four performances.

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The band is scheduled to perform a show at The Roxy on Thursday night, and promoted the show Wednesday morning.

ET has reached out to the band's rep for comment.