6:05pm PT by Michael O'Connell
Boston Marathon Bombing: NBC Swaps 'Revolution' for Brian Williams Special
Following an afternoon of preempted programming on cable news and broadcast networks to cover the bombing at the Boston Marathon, most of the primetime schedule is proceeding as planned.
STORY: Boston Marathon Bombing: News Networks Break In for Coverage
NBC is the sole exception, with the previously planned original episode for Revolution shelved in favor of a NBC News special. The 10 p.m. hour will be devoted to coverage of the explosions and anchored by Nightly News host Brian Williams. His regular telecast was extended by a half-hour.
ABC's World News Tonight also was extended by a half-hour, though the primetime block of Dancing With the Stars and Castle is airing as planned. Boston-area native and Dancing host Tom Bergeron, joined by Brooke Burke, opened the live-performance show by extending their thoughts and prayers to the city.
The regular block also is airing on CBS, though the network did extend its nightly Evening News broadcast by a full hour. Scott Pelley anchored coverage for the network throughout the day.
Fox, which does not have as big of a footprint in the news sphere, is airing its two-hour primetime block as planned -- though affiliates do have the option to pre-empt it in favor of local news coverage.