Updates headline

March 21 (Reuters) - Britain's Heathrow Airport said on Friday it will remain closed through the day after a huge fire at a nearby electrical substation wiped out power, disrupting flight schedules of global airlines.

According to flight tracking website FlightRadar24, at least 120 inbound flights to Heathrow, Europe's busiest airport, were being diverted to other airports.

Here are the top 10 airlines by capacity that were set to arrive at Heathrow airport on Friday.

Here is what airlines are saying about the closure:

• British Airways: "Due to a power outage in the London Heathrow area, London Heathrow Airport is currently closed. As a result, customers due to travel from Heathrow on Friday are advised not to travel to the airport until further notice. This will clearly have a significant impact on our operation and our customers and we’re working as quickly as possible to update them on their travel options for the next 24 hours and beyond."

• United Airlines: "Seven United flights returned to their origin or to other airports, and Friday flights to London Heathrow are being cancelled. We are working with our customers to offer alternative travel options."

• Air India: "London Heathrow-bound AI129 from Mumbai is returning to Mumbai; AI161 from Delhi is diverting to Frankfurt. All our remaining flights to and from London Heathrow, including AI111 of this morning, have been cancelled for 21 March."

• Aer Lingus: "Cancelling all flights to and from London Heathrow Airport until further notice today following the closure of the airport by the authorities."

• Virgin Atlantic: "This has had a significant impact on our flying programme both into and out of Heathrow and all Virgin Atlantic arriving and departing flights are cancelled until midday on 21 March, with the rest of today’s schedule currently under review."

• Qantas: "Our Singapore-London and Perth-London services were diverted to Paris today, with buses arranged to take customers on to London."

• Scandinavian Airlines System: "All our 12 round trips are so far cancelled to and from Heathrow. We will keep affected passengers informed.

• Ryanair: Ryanair in a post on X said it had added up to 8 rescue flights between Dublin and London Stansted, to rescue passengers affected by Heathrow's closure.

• Singapore Airlines: A spokesperson for the airline said four flights from Singapore to London were affected, and four flights from London to Singapore have been cancelled.

Source: Data from Cirium Ascend, company statements.

Note: The seats represent capacity, not ticketed passengers.

(Reporting by Raechel Thankam Job, Abhijith Ganapavaram, Jamie Freed, Surbhi Misra, Angela Christy, Devika Nair and Chandini Monnappa)

((Chandini.M@thomsonreuters.com; +918061822697;))