A London City Hall committee has warned that Heathrow Airport's expansion plans would undermine progress made to the capital's air quality and expose residents to "harmful" levels of noise, in a letter to the government.

One man was arrested after a substance that appeared to be pepper spray was used during a fight in one of the airport’s parking garages, the police said.

A three-year-old girl is among 21 injured after a pepper spray attack at Heathrow Airport, when a woman was robbed of her suitcase, according to police.

The first flight will depart from Seattle on May 21.

Police have arrested a man in London after a group of people were assaulted with pepper spray in a parking garage at Heathrow Airport.