An additional two individuals have been arrested in connection with a theft at London's Heathrow Airport in which 21 people were injured by a substance believed to be pepper spray, according to police.
A 24-year-old man, was arrested in Lambeth for suspected robbery and assault and a woman, 23 was arrested for suspected conspiracy to commit robbery. Both individuals are still being held, the force said.
The arrests come after a probe into an attack at the multi-level parking garage at Heathrow's Terminal 3 on Sunday. Before the incident, a pair of female travelers had stolen from them their luggage upon exiting a parking garage elevator.
A three-year-old girl was among the those hurt in the event. Five people were taken to the hospital for treatment and were later discharged.
Officers arrested a man in his thirties on suspicion of theft and assault near the scene. He was subsequently released pending further inquiries as the investigation proceeds.
Authorities were called at approximately 08:10 GMT following reports of a number of people hurt by a noxious substance thought to be pepper spray.
The assault - which police said was a standalone incident and not considered an act of terror - resulted in delays to rail services and the temporary shutdown of the Central Terminal Area tunnel and the Terminal 3 car park for a short time.
