Power circuits are currently be reconnected to bloody huge generators. Looks like this could be a long outage.
From UKPN:
Update at 19:13 - Our engineers are continuing to work with emergency services to tackle a fire in a tunnel in the Kingsway area. At this stage our plan will be to restore the majority of customers by using several large generators. However due to the severity of the fire and the developing situation it is unlikely that power will be restored tonight. We apologise for the impact this will have, we'll work to restore power as quickly as is safely possible.