NBC's Tim Russert has died of an apparent heart attack.

The network says its Washington bureau chief and host of "Meet the Press" collapsed and died at work Friday. Russert was 58. He becme host of "Meet the Press" in 1991 and turned it into the most widely-watched program of its type in the nation. He became known for an unrelenting style of questioning.

In announcing the death on NBC, longtime colleague Tom Brokaw said Russert's death came during a political campaign that "he loved." He called Russert a "beloved colleague" and "one of the premier journalists of our time."

Tim Russert is best known for his aggressive questioning that helped turn "Meet the Press" into the most widely watched Sunday morning interview show in the nation.

He took the helm of "Meet the Press" in December of 1991. He brought with him a Jesuit education, a law degree, and experience as an aide to the late Democratic Senator Daniel Patrick Moynihan of New York.
The native of Buffalo, New York, became known for a relentless style of questioning that made some politicians reluctant to appear. But they were confident that they could claim extra credibility if they survived his grilling intact.

Washingtonian magazine once dubbed him the best journalist in town, and described "Meet the Press" as "the most interesting and important hour on television." This year, Time magazine named him one of the 100 most influential people in the world. Russert also wrote the best-selling books "Big Russ and Me," in 2004, and "Wisdom of our Fathers," in 2006.

Russert was married to Maureen Orth, a writer for Vanity Fair. They had one son, Luke.