An additional two individuals are now in custody related to a theft at London's Heathrow Airport where 21 people sustained injuries by a substance believed to be pepper spray, as stated by law enforcement.
A 24-year-old man, was arrested in Lambeth for suspected theft and assault and a 23-year-old woman was detained for suspected conspiring to commit a robbery. Both individuals remain in custody, the force said.
These detentions follow 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 were robbed of their luggage after getting out of a car park lift.
A toddler aged three was one of the injured during the incident. Five people were taken to the hospital for treatment and were later discharged.
Officers detained a 31-year-old man for suspected robbery and assault close to the scene. He has since been released under investigation while inquiries continue.
Authorities were called at approximately 8:10 in the morning GMT after reports came in regarding a number of people injured by an irritating chemical thought to be pepper spray.
The attack - an event that police said was isolated and not considered an act of terror - caused train delays and the partial closure of the main airport tunnel and the Terminal 3 parking facility briefly.
