London power cut: Underground cable fault leaves thousands of buildings without electricity

A major power cut has hit large parts of London, leaving thousands of businesses and homes without electricity and disrupting some of the capital's busiest transport links.

The outage, which began at around 10.30am on Monday, was caused by a fault on an underground electricity cable. UK Power Networks confirmed that the issue has affected 32 postcodes across north, east, and central London, including parts of Islington, Hackney, Westminster, and the City of London.

As the blackout struck, offices in the capital’s financial heart were suddenly plunged into darkness. At Finsbury Square, near Moorgate, one worker described how the power cut killed lights, computer screens, and Wi-Fi connections instantly.

"All power went off, including all the lights and TVs and Wi-Fi," they said, describing the sudden change. "It was incredibly eerie and silent, and we could see through the glass atrium that all the floors in the building had lost power."

Transport services disrupted

The disruption quickly spread to the transport network, causing immediate confusion for morning travellers. Liverpool Street, which is the busiest railway station in the UK, was left with blank information screens. Crowds of confused passengers were left milling around the concourse, unable to see when or where their trains would depart.

Nearby, train services on the Great Northern line were disrupted by darkness on the platforms. The operator announced that its trains would not stop at Essex Road station because the platform lighting had completely failed. Great Northern warned passengers that they would need to travel via Old Street or Highbury & Islington to complete their journeys, advising them to allow extra time.

Network recovery underway

Engineers from UK Power Networks have been sent to local substations to investigate the fault and reroute the electricity supply. The network operator said it has managed to restore electricity to 4,989 customers so far, but thousands of other properties remain without power. The company initially estimated that remaining properties should have their power restored between midday and 1.00pm on Monday.

The affected zone stretches across a massive swathe of London. Postcodes from residential streets in Hackney and Islington to the dense commercial blocks of the City and the tourist areas of Westminster have been hit, leaving small businesses and multinational offices alike struggling to operate without internet or lights.

The incident shows how quickly a single failure in underground infrastructure can disrupt the daily operations of the capital, bringing offices and transport hubs to a standstill on a busy Monday morning. It is not yet clear how long the full recovery of the local network will take if further faults are found.