At 58, Russert Collapses At NBC's News Bureau:

Tim Russert, NBC journalist and political heavyweight host of "Meet the Press," has died after collapsing at NBC's Washington news bureau, a source said. He was 58 years old.

In his role as host of the seminal Sunday morning political program "Meet the Press" - which he took over in 1991 - he became renowned for his hard-nosed interviews where he frequently cornered some of Washington's cagiest political figures with tough questions.

The industry is quite obviously in shock as no one saw this coming. Russert was actually recording promotional clips for Meet the Press when he had this fatal heart attack. He was an amazingly influential figure in the political world. Meet the Press will never be the same.

He will be missed...

Additional details to follow...