Flights have officially left Heathrow Airport in London following a day of chaos yesterday. The major airport had to close on Friday following a huge fire at a substation which led to an "unprecedented" loss of power.

The incident caused chaos worldwide, with flights being cancelled and thousands of people diverted to other airports. More than 1,300 flights were unable to take off or land at Heathrow. The airport's chief executive Thomas Woldbye apologised and airport officials said today: "Flights have resumed at Heathrow following yesterday's power outage.

"If you're due to travel today, we advise you to still contact your airline for your latest flight information before heading to the airport. We apologise for the disruption and appreciate your patience whilst operations return to normal."

Although a spokesperson confirmed Heathrow is "open and fully operational today", there have been some cancellations this morning and it is understood that flights will not be back to normal until midweek.

The BBC reports that nine flights of the first 20 of the day were cancelled this morning. British Airways said it believes 85% of its flights would run today, but with delays.

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