Two more people are now in custody in connection with a robbery at London's Heathrow Airport where 21 people were injured by what is thought to be pepper 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, authorities confirmed.
The arrests follow an investigation into an attack at the multi-storey car park at Terminal 3 this past Sunday. Before the incident, a pair of female travelers were robbed of their suitcases upon exiting a parking garage elevator.
A toddler aged three was among the injured during the incident. A total of five individuals were taken to the hospital for treatment and have since been released.
Officers arrested a man in his thirties on suspicion of theft and assault close to the scene. He was subsequently released pending further inquiries as the investigation proceeds.
Authorities were alerted at about 8:10 in the morning GMT after reports came in regarding several individuals injured by an irritating chemical believed to be an irritant spray.
The assault - an event that police said was isolated and not being treated as terrorism - caused train delays and the partial closure of the main airport tunnel and the Terminal 3 parking facility briefly.
