Two more people are now in custody in connection with a robbery at Heathrow Airport where 21 people were injured by a substance believed to be an irritant spray, according to police.
A man, 24, was arrested in Lambeth for suspected theft and assault and a woman, 23 was detained on suspicion of conspiracy to commit robbery. Both individuals are still being held, the force said.
The arrests come after an investigation into an assault at the multi-storey car park at Heathrow's Terminal 3 on Sunday. Before the attack, two women were robbed of their suitcases upon exiting a parking garage elevator.
A three-year-old girl was among the those hurt during the incident. A total of five individuals were taken to the hospital for treatment and have since been released.
Officers arrested a 31-year-old man on suspicion of theft and assault close to the scene. He has since been released pending further inquiries as the investigation proceeds.
Police were alerted at approximately 08:10 GMT after reports came in regarding a number of people injured by an irritating chemical believed to be pepper spray.
The attack - which authorities stated was isolated and not considered terrorism - resulted in delays to rail services and the partial closure of the main airport tunnel and the T3 car park for a short time.
