London — Again

It looks like there has been another attack on London: three underground stations -- Warren Street, Shepherd's Bush, and Oval -- appear to have been hit by explosions of some sort. While information is sketchy, at the moment, these three Tube stations have been evacuated. There was also an incident on a bus, which had its windows blown out. There is a report of a nail bomb exploding. No reports of any casualties so far. Developing.... UPDATE: Police have entered London's College University Hospital, and cordoned it off. UPDATE II: There's a suspect.