
A man has been arrested after what emergency services described as a "potential hazardous materials incident" at Heathrow Airport.
The west London airport's Terminal 4 check-in area was evacuated on Monday, after around 20 people reported injuries.
Specialist officers attended the scene alongside the London Fire Brigade and London Ambulance Service and conducted a thorough search of the area.
Following the search, Metropolitan Police officers located a canister of what is believed to be CS spray.
"It is thought that this substance caused a reaction to those within the airport," the Metropolitan Police said in a statement.
The force said a 57-year-old man had been arrested on suspicion of possession of a firearm (CS spray) and causing a public nuisance.
More from Sky News:
Woman dies after small boat rescue
Alleged notes in Epstein birthday book from Trump and Mandelson
He remains in police custody. The incident is not being treated as terrorism related.
London Ambulance Service said one person had been taken to hospital following the incident.
(c) Sky News 2025: Man arrested after Heathrow Airport incident that sparked evacuation of terminal