Tim Russert by Virginia Sherwood/MSNBC Photo Tim Russert by Virginia Sherwood/MSNBC Photo

Tim Russert died on Friday of an apparent heart attack after collapsing at NBC's Washington bureau, where he was recording voiceovers for this weekend's Meet the Press. He was 58.

In reporting on-air on the passing of his "beloved colleague," Tom Brokaw said, "This news division will not be the same without his strong, clear voice." Added Brian Williams in a Friday MSNBC newscast, "[Tim] was as addicted to his work as anyone I know. It was his life's love."

Russert - NBC News' senior vice president and Washington bureau chief - among his other accomplishments had moderated Meet the Press since December 1991. Meet the Press is the longest-running program on network television, having made its NBC-TV debut on November 6, 1947.

Russert served as Sen. Daniel Patrick Moynihan's chief-of-staff and former New York Governor Mario Cuomo's press secretary before crossing over into journalism and joining NBC News in 1984.

In remembering Russert, NBC News' chief foreign affairs correspondent Andrea Mitchell called him a "father figure" to many, saying that "when people were in trouble, when people had any sort of problem, he was the first person you would go to."

Off-air NBC staff are also remembering Russert as one of their own. NBC CEO Jeff Zucker expressed the collective heartbreak over the loss, saying, "The enormity of [it] cannot be overstated." NBC News prez Steve Capus said that Russert's passing is a loss to the entire nation: "Everyone at NBC News is in shock and absolutely devastated. He was our respected colleague, mentor, and dear friend." GE chief Jeff Immelt tributed Russert as "a wonderful human being."

Known for his hard-hitting interviews, Russert this past year was named by Time as one of the world's 100 most influential people. He moderated several of the recent presidential debates and is author of the best-selling books Big Russ and Me and Wisdom of our Fathers.

Russert is survived by his wife, Maureen Orth (a writer for Vanity Fair), and their son Luke, as well as his own father, Russ. - Matt Mitovich

Use our Online Video Guide to remember Russert's fine work.

More on Russert:
" Matt Roush Remembers TV's Political Enthusiast
" TV Guide's Last Interview with Tim Russert