A New Year's Eve knife attack at a station in Manchester in which three people were injured as a terror incident, police have said.
Counter terror officers continue to question a 25-year-old man, who is being held in connection with the incident at Victoria Station in the centre of the city, officers said on Tuesday.
Officers also conducted a search of the suspect’s home, in the Cheetham Hill neighbourhood in northern Manchester.
Greater Manchester Police (GMP) chief constable Ian Hopkins said the attack was being treated as a “terrorist investigation”.
Three people - a police officer in his 30s and a man and a woman in their 50s - were taken to hospital to be treated for stab wounds, none of which were thought to be life-threatening.
Witnesses reported the suspect shouted “Allah” and “long live the Caliphate” during the incident, which took place on a tram platform at the station just before 9pm on Monday evening.
A joint statement by Greater Manchester Police and the British Transport Police (BTP) said a suspect was arrested on suspicion of attempted murder on a tram platform at the station “within minutes” of the incident taking place.
BTP assistant chief constable Sean O'Callaghan paid tribute to the officers who had first been on the scene.
“I am incredibly proud of the four officers who were immediately on scene last night, detaining a man who was wielding a knife,” he said. “They were fearless, running towards danger and preventing further harm coming to passengers.
“Unfortunately however, one of our police officers suffered a stab injury to their shoulder and we're all relieved that this is not more serious.
“It is good news that he has now been discharged from hospital, we are all wishing him a speedy recovery.”
Theresa May and Jeremy Corbyn have both praised the response of emergency services staff who dealt with the attack.
“My thoughts are with those who were injured in the suspected terrorist attack in Manchester last night,” the prime minister said in a statement on Twitter.
“I thank the emergency services for their courageous response.”
“Thinking of those injured in Manchester last night, their families and loved ones,” the Labour leader added.
“Thanks to our emergency services for their professionalism and bravery in dealing with this suspected terror attack.”
Police say there is no indication any other individuals were involved in planning or assisting the attack.
Investigators said the incident is “not going” and there is currently no intelligence to suggest there is a wider threat to the public.
Manchester Victoria station re-opened on Tuesday afternoon.
Additional reporting by agencies