An additional two individuals are now in custody in connection with a robbery at London's Heathrow Airport in which 21 people were injured by what is thought to be an irritant spray, according to law enforcement.
A man, 24, was arrested in Lambeth on suspicion of theft and assault and a woman, 23 was detained for suspected conspiracy to commit robbery. Both individuals are still being held, the force said.
The arrests come after a probe into an attack at the multi-level parking garage at Heathrow's Terminal 3 on Sunday. Before the incident, two women were robbed of their suitcases upon exiting a car park lift.
A three-year-old girl was one of the injured during the incident. Five people were taken to the hospital for treatment and were later discharged.
Officers detained a 31-year-old man on suspicion of theft and assault close to the location. He has since been released under investigation while inquiries continue.
Police were alerted at about 08:10 GMT following reports of a number of individuals injured by an irritating chemical thought to be an irritant spray.
The attack - an event that police said was isolated and not being treated as terrorism - resulted in train delays and the temporary shutdown of the Central Terminal Area tunnel and the T3 parking facility for a short time.
