Charles Clarke has spoken in The Commons (1pm) - confirming four explosions. Three on tube trains and the bus. Edgware Road explosion at the station. The other two were on trains between stations - hence the casualities / smoke etc at groups of stations.
A recue operation is on going in a tunnel outside of King's Cross station.
Investigations ongoing in South Kensington and Marleybone. What that means is unclear.
Eyewitess report from staff at the BMA (outside the Bus incident) suggest a terrible scene - a great deal of work by paramedics must be going on out of sight and underground.