Mark Knoller, a longtime White House correspondent for CBS News, has died, according to the network. He was 73. A cause of death was was not disclosed, but he had reportedly suffered from diabetes and was in poor health.

“Mark Knoller was the hardest-working and most prolific White House correspondent of a generation,” Tom Cibrowski, president and executive editor of CBS News, said. “Everyone in America knew his distinctive voice and his up-to-the-minute reporting across eight Presidential administrations.”

Born in Brooklyn, New York, on Feb. 20, 1952, Knoller worked at WNEW Radio and the Associated Press Radio Network before moving to CBS, where in just a few years he became the White House correspondent for CBS Radio.

Knoller covered the administrations of Presidents George H.W. Bush, Bill Clinton, George W. Bush, Barack Obama, and Donald Trump. He left CBS in 2020, telling the Washington Examiner that he was laid off.

“Mark Knoller was the heart and soul of the White House press corps, bringing unmatched passion to a beat he loved,” said White House Correspondents Association President Weijia Jiang. “He wasn’t just one of the most trusted voices covering the presidency — he was also the colleague you could always count on for help, perspective, or a bit of good humor.”