India, Dec. 7 -- Parts of London's Heathrow Airport were briefly locked down on Sunday after a man assaulted a group of people with pepper spray after an argument.

Police said that the man was arrested, adding that the incident was not being treated as a case of terrorism, reported news agency AFP.

The incident occurred at Terminal 3's multi-storey car park of the Europe's busiest airport after an argument between "a group of people known to each other", London's Metropolitan Police said.

The authorities said 21 people were being treated at the scene and five were taken to the hospital, while the suspect was taken into custody.

Police said all the injuries were "not believed to be life-changing or life-threatening".

London's Metropol...