As the BBB said, there were a series of attacks on the London Underground this morning (as well as a double-decker bus). No confirmed perpetrator yet, but the press conference officials weren't talking about that either, asking questions to be restricted to the relief efforts.
The attacks, however, do fit the Al Qaeda-associated organization profile: early morning, coordinated, aimed at a well-known symbol of a country involved in the Middle East. (I may be wrong about the early morning thing, considering the Cole bombing.)
They said that it was sad but unsurprising- they had drilled for this, and thus were able to quickly act to aid the victims.
One organization called "the Secret Organisation Group of Al-Qa’ida of Jihad Organisation in Europe" on the Al Qal'ah (The Fortress) website has claimed resposibility after the fact. Could be true, could be a distraction, could be nonsense. Since Al Qaeda didn't take credit for 9/11, I'm not convinced yet.