A plane departing Heathrow Airport had to return after a laser was shone at the cockpit, causing a medical issue with a pilot.

The Virgin Atlantic flight doubled back as a "precautionary measure" due to the co-pilot feeling unwell, the airline said.

Police are were trying to find the source of the beam, but it is believed to have been shone from around six miles west of the airport.

The British Airline Pilots Association has called for lasers to be classed as offensive weapons, with several such incidents occurring recently.

A Metropolitan Police spokesman said: "Police were contacted at approximately 9.35pm on Sunday, February 14 following reports of a laser shone in the direction of a commercial flight that had taken off from Heathrow Airport.

"Inquiries continue to establish where the offence took place. There have been no arrests."

An audio recording from the cockpit of the flight revealed their plans to double-back were due to a 'medical issue' with the pilot.

A Virgin Atlantic spokeswoman confirmed the VS025 flight returned to “ as a precautionary measure due to a laser beam incident.”

The flight was heading towards New York JFK airport.

First Officer 'unwell'

The spokeswoman said: "The safety of our crew and customers is our top priority and we apologise for any inconvenience to those on board.

"All customers will be offered overnight accommodation and we will get them on their journey as soon as possible. We are working with the authorities to identify the source of the laser that caused the return of the aircraft to Heathrow."

A message on the airline's flight status website added: "Following this incident the First Officer reported feeling unwell.

"The decision was taken by both pilots to return to Heathrow rather than continue the transatlantic crossing."