Official sources have stated 21 people have been killed at King's Cross and ambulance sources suggest: nine at Edgware road, seven at Aldgate, two at Russell Square. There are hundreds - possibly more than a thousand - injured.  A large portion of these injuries are believed to be minor however, with many people treated primarily on the scene.
CNN, the BBC and ITV News have confirmed 2 fatalities at Aldgate Station. At least 90 casualties have been reported from Aldgate Station alone. All major London hospitals have been placed on alert, and are currently not accepting non-emergency cases. 95 casualties were taken by bus to the Royal London Hospital where they are being treated; 10 are in critical condition. Many others are being treated at St Mary's Hospital, Paddington. Individuals who are wounded and walking are being treated at the scene; an eyewitness reported that they were "operating on injured people on the concourse at Liverpool Street station." . Paramedics were sent down into the tube system to search for more casualties. St. John Ambulance was called out to assist the London Ambulance Service , and hospitals had to call in off-duty staff.
Virgin Radio is reporting 45 dead. The BBC interviewed a doctor at the site of the bus explosion in Tavistock Square who said that 10 people had died there, though this remains unconfirmed. ITV News reports that it understands 8-10 people were killed at Edgware Road station. A Government spokesman is talking of 20 people dead.  and emergency services have told CNN that there are "double digit" fatalities still underground at King's Cross.
Recent reports state that 300 casualties (208 at Royal London Hospital alone ) are being treated in hospital and 150 of those are in a serious condition. Many are foreign nationals.
Confirmed current casualties (Police press conference):
Aldgate East Station at least 7 killed
King's Cross Station at least 21 killed
Edgware Road Station at least 5 killed