An additional two individuals are now in custody related to a theft at London's Heathrow Airport where 21 people were injured by a substance believed to be pepper spray, as stated by police.
A man, 24, was taken into custody in the Lambeth area for suspected theft and assault and a woman, 23 was arrested on suspicion of conspiring to commit a robbery. They both remain in custody, the force said.
The arrests follow an investigation into an assault at the multi-storey car park at Heathrow's Terminal 3 this past Sunday. Before the incident, a pair of female travelers had stolen from them their suitcases after getting out of a car park lift.
A three-year-old girl was one of the those hurt during the incident. Five people went to hospital for medical care and have since been released.
Police arrested a man in his thirties for suspected robbery and assault near the scene. He was subsequently released under investigation while inquiries continue.
Police were alerted at approximately 8:10 in the morning GMT following reports of a number of individuals hurt by an irritating chemical thought to be an irritant spray.
The attack - an event that police said was a standalone incident and not being treated as an act of terror - resulted in delays to rail services and the partial closure of the Central Terminal Area tunnel and the Terminal 3 car park for a short time.
