An additional two individuals are now in custody in connection with a robbery at London's Heathrow Airport in which 21 people sustained injuries by a substance believed to be an irritant spray, according to police.
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 are still being held, the force said.
These detentions follow an investigation into an attack at the multi-level parking garage at Terminal 3 on Sunday. Before the incident, two women were robbed of their suitcases upon exiting a car park lift.
A three-year-old girl was among the injured in the event. Five people went to hospital for treatment and have since been released.
Officers detained a 31-year-old man for suspected robbery and assault near the location. He has since been released pending further inquiries while inquiries continue.
Authorities were alerted at about 8:10 in the morning GMT following reports of several individuals hurt by an irritating chemical believed to be pepper spray.
The attack - an event that authorities stated was isolated and not considered an act of terror - resulted in delays to rail services and the partial closure of the Central Terminal Area tunnel and the T3 parking facility for a short time.
