Two more people 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, as stated by police.
A man, 24, was arrested in the Lambeth area on suspicion of theft and assault and a 23-year-old woman was detained for suspected conspiracy to commit robbery. They both remain in custody, the force said.
These detentions follow a probe into an assault at the multi-level parking garage at Terminal 3 on Sunday. Before the attack, two women were robbed of their luggage upon exiting a parking garage elevator.
A three-year-old girl was among the those hurt in the event. Five people went to hospital for medical care and were later released.
Police arrested a 31-year-old man on suspicion of theft and assault close to the scene. He has since been released under investigation while inquiries continue.
Authorities were called at approximately 08:10 GMT after reports came in regarding a number of individuals hurt by an irritating chemical thought to be pepper spray.
The assault - which police said was a standalone incident and not being treated as an act of terror - caused delays to rail services and the partial closure of the Central Terminal Area tunnel and the T3 car park briefly.
