Three separate signals failures caused widespread travel chaos on the Tube today.
The signals went down at Westminster and Temple causing major disruption for tens of thousands of commuters on two of the busiest lines, the District and Circle..
All Circle line services were affected in both directions.
There were severe delays to the District right through central London between Earl's Court and Whitechapel.
The two lines are used by nearly one million passengers a day.
Delays continued into the morning peak.
A third signal failure then forced the part suspension of Bakerloo line services towards the end of the peak.
There was no service between Lambeth North and Elephant & Castle due to the problem at Elephant & Castle. There were knock-on delays to the rest of the route.
Nigel Holness, London Underground (LU) Operations Director, said: "LU engineers have been on site at Embankment working to fix a signal circuit problem which was affecting eastbound trains trying to leave Westminster and westbound trains leaving Termple.
"Our technicians have quickly located the problem and we are now working to restore service levels as soon as possible. There are delays to District and Circle line services in the meantime, and I apologise to customers whose journeys have been disrupted this morning."
Minor delays to both District and Circle line services ocntinued throughout the peak.
It was the second successive day of delays for District line users with service disrupted yesterday due to a signal failure at Bromley by Bow.
Southern mainline rail services through West Croydon to Victoria and London Bridge were delayed due to a broken down train at West Croydon.
