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.”

Countless former colleagues described Knoller as a world class journalist with an unrelenting work ethic who was committed to simply reporting the facts for his audience.

He was known in Washington as the unofficial presidential archivist thanks to his encyclopedic knowledge of the White House and the presidency, chronicling details such as how many times a president had gone golfing or had answered questions from the press.

“Mark represented the best of the White House press corps,” said AP Executive Editor Julie Pace, who worked alongside Knoller as the AP’s chief White House correspondent. “He demanded the same level of accountability and transparency from every president he covered, regardless of party. He carried out his work in the spirit of true public service, sharing his meticulous records of the presidency with any colleague who asked for a data point.”

Pace recalled how she “took advantage of his record keeping numerous times as a reporter” and was “always grateful for both his generosity and dedication to his craft.”

Nancy Benac, the AP’s former White House editor, recalled that “you could go to Mark with any question, and he had the answer.”

Mark Smith, who worked with Knoller at AP Radio and for nearly two decades as an AP White House correspondent, described their relationship as “competitors/comrades.” He said that Knoller “was famous for keeping brutal hours” and on foreign trips “was almost always the last person in the filing center — and there again to open it in the morning.”

Smith continued: “As a result presidents got used to seeing him and familiar with his booming voice asking questions. He was blunt and to the point, persistent but not hectoring. He absolutely loved getting a rise or a laugh out of the president (and I’m thinking here of Clinton, Bush and Obama), but he also never accepted casual evasion.”

Indeed, Knoller’s stellar reputation extended not just to his fellow reporters in the press corps, but to the administrations he was covering.

“Mark was a gem of a man and the definition of what a good reporter should be,” said Ari Fleischer, who served as White House press secretary under Bush from 2001 to 2003. “Mark never betrayed any bias, any personal views. He was probably of the last generation of reporters who viewed their job as just telling the news with no inkling at all of their personal thoughts.”

Fleischer, who described Knoller as “the classic old school, get the story, get it right reporter,” also recalled his “booming voice” and penchant for compiling statistics that he frequently shared with his competition. He spoke of Knoller’s love for Crawford, Texas, home of the Bush family ranch, and how the Brooklyn native fit in seamlessly.

Above all though, Knoller is remembered by those who knew him as a thoughtful, generous and funny man in a town known for egos and power.

Benac pointed to his “amazing sense of humor” with dry zingers that would land minutes later. She described him as “just a wonderful person and a wonderful journalist.” For Smith, what set Knoller apart was his “playfulness.” Fleischer called him “one of the kindest, most courteous, modest people in the press corps.”

“You know I’m smiling as I think about him even though this is really hard because Mark kept the humanity in the White House for me,” said Ben Feller, who worked with Knoller as the AP’s chief White House correspondent. “He knew it was always about the people, even in that deeply intense beat where it feels like the whole world’s happening in that briefing room.”