Parts of London and the southeast of England have been hit by a large-scale power cut.
UK Power Networks has said: “We believe this is due to a failure to National Grid’s network, which is affecting our customers.”
It owns and maintains the electricity cables in southeast England, the east of England and London.
The power outage has caused widespread traffic disruption on the roads and railways.
Transport for London said that some traffic lights were not working and it advised caution on the roads.
Police officers could be forced to man busy junctions where traffic lights have been shut down.
London North Eastern Railway tweeted: “Due to a problem under investigation between #Stevenage and #KingsCross, all lines towards London are blocked.
“Train services running to and from these stations may be cancelled or delayed by up to 60 minutes.”
Rail operator Thameslink said many of its trains were “at a stand”.
A tweet said: “The power network has failed in the large parts of London and the South East.
“This has prevented our trains between Farringdon and Bedford from being able to take power and as a result, most of our trains are currently at a stand.”
Western Power Distribution (WPD), the electricity distribution network operator for the midlands, southwest and Wales, said there was a “major incident”.
A WPD tweet said: “We are currently experiencing a major incident on the national electricity infrastructure.
“We are in the process of restoring customers now and will provide further updates as soon as possible for specific areas. We are sorry for the inconvenience this is causing.”
A Network Rail spokeswoman said: “There was a power surge on the national grid this evening which means we lost power to all our signalling over a wide area, including the Newport, Gloucester, Ashford, Bristol, Eastbourne, Hastings, Three Bridges and Exeter areas.
“All trains were stopped while our back-up signalling system started up.
“While most of our signalling system has come back online and trains are running, there will be delays to journeys in these areas.”
Elsewhere, Cheshire Police tweeted: “We’re aware of a power outage in the Ellesmere Port area, including in Great Sutton and Little Sutton.”
Merseyrail said all services on the Wirral Line around Liverpool are suspended.
Source:: Daily Times