Police are treating the stabbing at Leytonstone Tube station as a terrorist incident as they appealed to the public for information.

Detectives from the Metropolitan Police's Counter Terrorism Command are investigating the incident after a man was taken to hospital with stab wounds.

Police were called at 7.06pm today (December 5) to reports of a number of people stabbed at the station and a man threatening other people with a knife.

One man has sustained serious knife injuries which are not believed at this stage to be life-threatening.

Two other people have sustained minor injuries.

Met officers attended the scene, arrested a man at 7.14pm and took him to an east London police station where he remains in custody.

A taser was used by police in the incident.

In videos posted online, a pool of blood can be seen next to the ticket barriers.

Commander Richard Walton, who leads the Met's Counter Terrorism Command, said: "We are treating this as a terrorist incident.

“I would urge the public to remain calm, but alert and vigilant.

"The threat from terrorism remains at severe, which means that a terrorist attack is highly likely.

"I would appeal to anyone who was in the vicinity of Leytonstone underground station earlier this evening at around 7pm who saw anything suspicious to call the Anti-Terrorist Hotline on 0800 789 321.

"Anyone who may have captured video or photographic footage of the incident is also urged to make contact with the Counter Terrorism Command via the Anti-Terrorist Hotline."

Transport for London (TfL) said the station remains closed and there are severe delays on the Central line after the incident.   

Steve Griffiths, London Underground's Chief Operating Officer, said: "Leytonstone station is currently closed whilst the police investigate an incident that occurred earlier.

"We're assisting the police as necessary and will reopen the station as soon as possible."