Two more people have been arrested following a robbery and assault at Heathrow Airport which left 21 people injured, including a three-year-old girl.

The Metropolitan Police confirmed that a 24-year-old man was arrested in Lambeth on suspicion of robbery and assault, while a 23-year-old woman was detained on suspicion of conspiracy to commit robbery yesterday (Monday, 8 December), with both remaining in custody.

The arrests form part of an ongoing investigation into an incident at the multi-storey car park at Terminal 3 on Sunday morning, when two women were robbed of their suitcases after exiting a lift.

During the attack, a noxious substance believed to be pepper spray was released, injuring 21 people. Five were taken to hospital for treatment and have since been discharged.

A 31-year-old man was previously arrested near the scene on suspicion of robbery and assault. He has since been released under investigation while enquiries continue.

Police were first called at around 8.10am on Sunday, 7 December, and the incident led to the temporary closure of the Terminal 3 car park and the Central Terminal Area tunnel.

The Met has confirmed it is being treated as an isolated incident and not terror-related.

Commander Peter Stevens said: "Our team have been working at pace today to review CCTV from the area and speak with witnesses at the scene.

"At this stage, it's understood that a woman was robbed of her suitcase by a group of four men, who sprayed a substance believed to be pepper spray in her direction.

"This occurred within a car park lift, with those in the lift and surrounding area affected by the spray.

"Our officers are working to determine the full circumstances around what happened but we do believe this to be an isolated incident with those directly involved known to each other.

"We appreciate that this has been a concerning incident and I commend the actions of the emergency services and members of staff at Heathrow Airport."

Enquiries remain ongoing and anyone with any information is asked to contact the investigation team on 101 quoting CAD 1803 7 DEC or anonymously via Crimestoppers on 0800 555 111.

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