Jordan Feldstein, the manager of Maroon 5 and other music stars, died Friday night of an apparent heart attack at age 40.

Feldstein, the older brother of actors Jonah Hill and Beanie Feldstein, was a childhood friend of Maroon 5 frontman Adam Levine and managed the group from its founding 15 years ago, according to Billboard.

“Unfortunately, last night Jordan called 911 for shortness of breath, when paramedics arrived it was determined he went into full cardiac arrest and passed away shortly thereafter,” his family said in a statement. “His family asks for privacy during this difficult and unexpected time.”

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Feldstein founded and served as CEO of Career Artist Management, whose clients also included Iggy Azalea, Miguel, Robin Thicke, Elle King and Big Boi.

He was briefly married to actress Francesca Eastwood, daughter of Oscar-winning actor and director Clint Eastwood and actress Frances Fisher. The marriage ended in annulment in 2013.

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Tributes began to pour in quickly online after news of his death went public.

“Jordan Feldstein was fiercely protective of his artists and their art and always delivered good or bad news personally. A mensch,” wrote Tidal VP Tony Gervino.

Awful news. Jordan Feldstein was fiercely protective of his artists and their art and always delivered good or bad news personally. A mensch. RIP. https://t.co/IKgDV8HXkS — Tony Gervino (@microtony) December 23, 2017

Horrible news this morning…RIP Jordan Feldstein… — Ron Perry (@theRonPerry) December 23, 2017