A man was airlifted to hospital with serious injuries after reports of a stabbing at a London tube station.
British Transport Police officers were called to Hainault Station, north-east London, at about 18:30 BST on Friday to reports a man had been attacked.
The injured man was taken to the Royal London Hospital in Whitechapel by air ambulance with what were believed to be serious injuries.
Hainault Station was cordoned off while police investigated.
Anyone with any information about the incident has been asked to contact British Transport Police.