Greater Manchester Police said they were keeping an open mind about the motive, adding there was no intelligence to suggest a wider threat.

A witness, a BBC producer who was at the station, said the man was armed with a large knife who linked his actions to "bombings in other countries". The suspect was arrested "within minutes", police said, and was being questioned in custody.

Those injured, a woman and a man in their 50s, were in a serious but not life-threatening condition, police said. A male police officer in his 30s who sustained a stab wound to his shoulder was released from hospital early on Tuesday morning.

Police said they would step up their presence in the city where a suicide bomb attack in May 2017 killed 22 people as they left an Ariana Grande concert.

"Tonight's events will have understandably worried people but I need to stress that the incident is not ongoing, a man is in custody and there is currently no intelligence to suggest there is any wider threat at this time," Assistant Chief Constable Rob Potts said in a statement.

Britain is on its second-highest threat level of severe, meaning an attack is considered highly likely. Security officials say they are facing record levels of work in countering Islamist militants as well as far-right extremists after four major attacks last year.

Sam Clack, the BBC producer, told BBC 5 Live radio: "I heard the man say, 'As long as you keep bombing these countries this is going to keep happening.'"

"It was very, very scary."

The cordon at Victoria Station, closed after the attack, will be lifted shortly, the police said on Twitter.

REUTERS