A knifeman who stabbed three people at a Manchester shopping centre has been arrested on suspicion of terrorism, Greater Manchester Police have said.

Police were called to the Arndale Centre at 11.15am this morning to reports of a stabbing.

The 41-year-old suspect was detained and three people were taken to hospital with stab injuries.

Witnesses described a scene of terror as shoppers, some with injuries, sought refuge in stores.

Officers from Counter Terrorism Police North West were called in to investigate, and at around 3.15pm, Greater Manchester Police Assistant Chief Constable Russ Jackson said the suspect had been arrested on suspicion of the commission, preparation and instigation of an act of terrorism.

He added that investigators did not believe anyone else to be involved in the attack.

The suspect was first arrested on suspicion of a serious assault, the force said.

Mr Jackson said the suspect had been armed with a large knife as he entered the Exchange Court of the shopping centre where he "lunged" at shoppers.

He said the first to intervene were two unarmed police community support officers who had been nearby, and who tried to confront the attacker who then chased them with a knife as they called for assistance.

He added: "Other officers both armed and unarmed quickly responded and within five minutes he was challenged and detained by armed officers on Market Street outside theArndale Centre.

"We do not know the motivation for this terrible attack. It appears random, is certainly brutal and of course extremely frightening for anyone who witnessed it."

Mr Jackson said the incident was "bound to bring back memories of the awful events of 2017".

He added: "Although the injuries are nasty, we are told that, thankfully, none are life-threatening."

He said the force had increased patrols in the area, but added: "We do not believe there is a wider threat at this time and we are hoping to return the city to normality by tomorrow morning."

Mr Jackson called on anyone who may have been present to send any images or footage they have taken to the GMP website.

Greater Manchester Police initially stated five people had been injured, but later amended the figure to four.

A 19-year-old woman and another woman for whom no age was given were both taken to hospital with stab injuries and their condition was described as stable by the force.

A man in his 50s was also hospitalised with stab wounds, while a woman in her 40s was treated by paramedics at the scene but was not stabbed.

North West Ambulance Service (NWAS) said one patient had suffered "serious" injuries adding that it had been stood down from the incident at 1.56pm.

One shop worker, who gave his name only as Jordan, 23, told the PA news agency: "A man was running around with a knife lunging at multiple people, one of which came into my store visibly shaken with a small graze.

"Soon after, security staff told all retail staff to close their doors and move the public to the back of the stores."

Prime Minister Boris Johnson said he was "shocked by the incident and my thoughts are with the injured and all those affected".

Bev Hughes, Greater Manchester's deputy mayor for policing, crime and fire, said: "I want to praise Greater Manchester's emergency services for their swift and professional action.

"Our thoughts are with the five people injured.

"The scene has been secured and all emergency services are engaged in ensuring public safety - the investigation is ongoing."