Two more people are now in custody in connection with a robbery at Heathrow Airport where 21 people sustained injuries by what is thought to be pepper spray, according to police.
A man, 24, was taken into custody in the Lambeth area on suspicion of robbery and assault and a 23-year-old woman was arrested on suspicion of conspiring to commit a robbery. Both individuals are still being held, the force said.
These detentions follow a probe into an attack at the multi-storey car park at Heathrow's Terminal 3 on Sunday. Prior to the incident, a pair of female travelers were robbed of their luggage upon exiting a car park lift.
A toddler aged three was among the injured during the incident. Five people were taken to the hospital for treatment and were later discharged.
Police detained a man in his thirties for suspected theft and assault near the location. He was subsequently released pending further inquiries as the investigation proceeds.
Authorities were alerted at about 8:10 in the morning GMT following reports of a number of individuals hurt by an irritating chemical believed to be an irritant spray.
The attack - which authorities stated was a standalone incident and not considered terrorism - resulted in train delays and the temporary shutdown of the main airport tunnel and the Terminal 3 parking facility briefly.
