An additional two individuals are now in custody related to a theft at London's Heathrow Airport in which 21 people were injured by a substance believed to be an irritant spray, according to law enforcement.
A 24-year-old man, was taken into custody in Lambeth on suspicion of robbery and assault and a woman, 23 was detained on suspicion of conspiracy to commit robbery. They both remain in custody, the force said.
The arrests come after a probe into an assault at the multi-storey car park at Terminal 3 on Sunday. Before the attack, two women had stolen from them their luggage after getting out of a parking garage elevator.
A three-year-old girl was one of the injured during the incident. Five people were taken to the hospital for medical care and have since been discharged.
Police detained a man in his thirties for suspected theft and assault near the location. He was subsequently released under investigation as the investigation proceeds.
Police were called at about 08:10 GMT following reports of a number of people injured by a noxious substance believed to be an irritant spray.
The attack - which authorities stated was a standalone incident and not being treated as terrorism - resulted in train delays and the partial closure of the Central Terminal Area tunnel and the T3 parking facility for a short time.