London Underground, the Metropolitan Police and the British Transport Police can now confirm that the three bombs which exploded on three Tube trains on Thursday 7 July went off simultaneously at around 08.50am
Explosions were as follows (in succession):
Circle line train number 204 heading eastbound from Liverpool Street
station to Aldgate station.
Circle line train number 216 travelling westbound heading from Edgware Road station to Paddington station.
Piccadilly line train number 331 travelling from King's Cross St Pancras to Russell Square southbound.
London Underground operates a system called TrackerNet which allows staff to observe electronically the movement of rolling stock on the Tube network. It is presently being introduced for all London Underground lines and is in full operation on the Circle line.
TrackerNet is a management information tool only and not a system on which to base safety critical decisions. This is complimentary to existing LU signalling and track systems which feed into the individual line control rooms.
After careful consideration of the recorded archive of realtime TrackerNet movements on the Circle line we can confirm the above for Circle line trains numbers 204 and 216 to have occurred within the space of one minute respectively.
TrackerNet is not yet live on the central section of the Piccadilly line. However, we can also confirm for Piccadilly line train 331 that the explosion occurred simultaneously at 08:50:00. Our evidence is based upon the precise time the Tunnel Telephone system went out of service.
It was this information supplied by London Underground which enabled the Police to confirm that the explosions occurred simultaneously and was a critical development in the hunt for the perpetrators of these terrorist attacks.
The events of Thursday morning were unprecedented. London Underground followed its well-practiced procedures to keep passengers safe based on the flow of information received.
First indications received by London Underground's Network Control Centre (NCC) at 08:50 of a problem on the network suggested a power supply problem affecting a large area as stations were reporting that some escalators had stopped and other station equipment was no longer working.
The Network Control Centre immediately treated this as a power supply issue and took actions to resolve the issue. At this stage NCC believed that the problem could be resolved and power would be restored by 09:15.
What we now know is that the power surge occurred as a direct result of explosions knocking the power supply out at the three incident sites.
At 08:51, the Central line called the NCC enquiring about a possible large noise or explosion onboard a train at Liverpool Street. At 08:52, the Metropolitan line confirmed that an explosion had taken place.
NCC believed this to be directly related to the ongoing power supply issue. Loud noises or explosions often accompany a power supply rupture.
At 08:53, London Underground commenced Gold Control (command and control person in charge of a serious incident on the Underground) in response to the first incident at 08:50.
On its own, a power surge is a major issue.
While this was being investigated, the NCC received a report at 08:59 indicating that a train departing Edgware Road station had hit the tunnel wall.
Further information came in quickly, including smoke and passengers self de-training and walking down the tunnel towards the nearest station, Edgware Road.
Sub-surface line managers immediately called the emergency services believing this to be a derailment.
At this time, London Underground believed that they were dealing with a major incident (derailment) and a serious power supply issue on the network.
The first call to the Metropolitan Police at 08:51 indicated that they were being asked to attend a person under a train incident caused by the derailment.
It wasn't until 09:17 that the Metropolitan Police received a call specifically stating than an explosion had occurred at Edgware Road. This explains the Metropolitan Police reporting that the Edgware Road explosion occurred at 09:17.
We now know this not to be the case as it has been proven that the three explosions on the Tube network occurred almost simultaneously. The various emergency services were either in attendance or on their way to Edgware Road. We also know that the train did not derail and hit a tunnel wall.
At 09:01, the Metropolitan line reported that a person may be under a train at Liverpool Street. This was the third issue that the Network Control Centre was now dealing with within a space of eleven minutes.
At 09:03, the Piccadilly line Duty Operations Manager receives reports of passengers running from King's Cross.
At 09:05, the NCC is advised of walking wounded at Edgware Road.
At 09:09, an engineer reports losing a high tension power cable between Mansell Street and Moorgate.
At 09:10, the Piccadilly line Duty Operations Manager reports to NCC a request for ambulances.
In the 20 minutes that had passed since 08:50, the Network Control Centre was now dealing with four separate issues (power supply, derailment at Edgware Road / person under train, person under train at Liverpool Street, loss of high tension power cable near Moorgate) and was receiving the appropriate co-ordinated response from LU, emergency services and suppliers.
At 09:11, the Piccadilly line Duty Operations Manager reports loss of traction current in Russell Square both east and westbound and that a loud bang had been heard at Russell Square westbound with staff already investigating.
By 0915, it was clear that the series of events occurring across the network were directly related to multiple explosions and a Code Amber alert was declared which means trains are brought into stations and told to stay there until further notice.
This was LU commencing the shutdown of the entire Tube network as it was evident that the continued operation of the Tube presented a risk to customers if further explosions occurred. LU staff began de-training large numbers of passengers and evacuating them from the network.
During the morning peak, LU operates over 500 trains and this is greater than the number of platforms on the network so some trains would have had to wait in tunnelled sections until they were clear to proceed into a station.
Where possible, trains in tunnelled sections joined together so that passengers could walk through from one train onto another until they reached a station.
The NCC asked all Underground lines to continue to hold all services and identify trains they had in stations and what was stalled in tunnel sections.
We then evacuated all remaining passengers from their trains - equivalent to a Code Red action - at 09:46 which means that all trains remained stationary, remaining passengers were detrained, stations commenced evacuation procedures and all services were suspended.
A Code Red, the immediate shutdown of the network, was never called.
As this would have left many passengers trapped in trains which would have been stalled in tunnels across the network.
The Code Amber action allowed the majority of passengers to be de-trained at stations rather than proceeding through tunnels which is a slow and dangerous process.
Between 08:45 and 09:00 on Thursday 7 July 2005, over 200,000 passengers would have been travelling on over 500 trains. The majority of passengers who were not killed or seriously injured were evacuated within one hour.
The three explosions presented a variety of complex operational issues for London Underground each requiring analysis and response.