All we've got now are preliminary reports, but indications are someone - or some group - is trying to pull a Spaniard on the British elections today. So far, there is no mention of casualties and the damage seems to be limited to some broken glass.
Best reason to vote Blair if there ever was one.
Good luck today.
Update 21.09: Police are questioning a Dutch worker. Wow. According to Reuters, he's not a suspect though.