An additional two individuals are now in custody related to a theft at Heathrow Airport in which 21 people sustained injuries by what is thought to be an irritant spray, according to police.
A 24-year-old man, was arrested in Lambeth on suspicion of theft and assault and a woman, 23 was detained on suspicion of conspiring to commit a robbery. They both are still being held, the force said.
The arrests come after a probe into an attack at the multi-storey car park at Terminal 3 this past Sunday. Prior to the attack, a pair of female travelers were robbed of their suitcases upon exiting a car park lift.
A toddler aged three was among the injured during the incident. A total of five individuals were taken to the hospital for medical care and were later discharged.
Officers detained a 31-year-old man for suspected theft and assault close to the location. He was subsequently released pending further inquiries 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 - an event that police said was isolated and not being treated as terrorism - caused train delays and the partial closure of the Central Terminal Area tunnel and the Terminal 3 parking facility briefly.
