An additional two individuals have been arrested in connection with a robbery 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 man, 24, was taken into custody in the Lambeth area on suspicion of theft and assault and a woman, 23 was arrested for suspected conspiracy to commit robbery. Both individuals remain in custody, authorities confirmed.
The arrests follow an investigation into an attack at the multi-level parking garage at Heathrow's Terminal 3 on Sunday. Prior to the attack, two women were robbed of their luggage after getting out of a parking garage elevator.
A three-year-old girl was among the injured during the incident. A total of five individuals went to hospital for medical care and were later discharged.
Police detained a 31-year-old man on suspicion of theft and assault near the scene. He was subsequently released pending further inquiries while inquiries continue.
Police were alerted at approximately 08:10 GMT following reports of a number of people hurt by a noxious substance thought to be pepper spray.
The assault - which police said was isolated and not being treated as an act of terror - resulted in train delays and the temporary shutdown of the Central Terminal Area tunnel and the Terminal 3 parking facility for a short time.
