This is a very brief video copied from Betamax onto VHS 26 years ago (all that remains I'm afraid) of the BBC's breaking news of the Challenger disaster on January 28th 1986. Surprisingly, it was reported first on the children's news programme Newsround, with Roger Finn rather than by the BBC's regular television news service.
Newsround was the first British television programme to break the news of the loss of Challenger on 28 January 1986.
Update 2014: Interestingly, the BBC contacted me about this clip a couple of years ago as they intended to do a programme about celebrities who were children at the time & who had seen Newsround on 28th January 1986 and how it had affected them. Apparently the programme does not exist in the BBC archive and this may be the only recording in existence. They wanted to use the original recording for the show, but the 2nd gen recording I have access to was too poor quality. I have a better and longer recording on Betamax tape somewhere, hopefully one day I will find it in my loft and upload it to Youtube.