An additional two individuals are now in custody related to a theft at London's Heathrow Airport in which 21 people sustained injuries by a substance believed to be pepper spray, as stated by law enforcement.
A 24-year-old man, was taken into custody in the Lambeth area for suspected robbery and assault and a 23-year-old woman was detained on suspicion of conspiracy to commit robbery. Both individuals are still being held, authorities confirmed.
The arrests follow a probe into an attack at the multi-storey car park at Heathrow's Terminal 3 on Sunday. Prior to the attack, a pair of female travelers were robbed of their suitcases after getting out of a parking garage elevator.
A three-year-old girl was among the injured during the incident. Five people went to hospital for medical care and have since been released.
Officers arrested a 31-year-old man for suspected robbery and assault close to the location. He was subsequently released pending further inquiries while inquiries continue.
Authorities were alerted at about 08:10 GMT after reports came in regarding several people hurt by an irritating chemical thought to be an irritant spray.
The assault - which police said was a standalone incident 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 Terminal 3 parking facility for a short time.