Warning – this article contains details some may find distressing.

Eyewitnesses have spoken of horrific scenes in the aftermath of the Southport attack, with one describing it as the “worst thing I’ve seen in my life”.

Two children died and nine suffered critical injuries in a knife attack on a Taylor Swift-themed dance class on Monday, prompting a local children’s hospital to declare a major incident. Two adults were also critically injured.

Colin Parry, owner of Masters Vehicle Body Repairs, which is next to where the workshop was being held, told BBC 5Live he was first aware of a commotion because a young man in a face mask was refusing to pay a taxi driver.

He said he and a customer confronted the man but that he asked them, “What are you going to do?”, and walked off.

A 17-year-old boy, from Banks in Lancashire, has been arrested on suspicion of murder and attempted murder.

• What we know so far about the “ferocious” Southport stabbings

Mr Parry said he went back to work but then received a call from an employee who had gone to the building next door because he heard children screaming, “and not like a normal play scream”.

“We all ran out and there’s young kids, all bleeding,” Mr Parry said.

He said many of the children were then ushered into a nearby home and that the scene outside was “mayhem”.

“It was the worst thing I’ve seen ever in my life,” he said.

“Why? Why would you do these things to these kids? It’s horrific.”

Mr Parry also told the PA news agency that he had heard mothers arriving on the street “screaming” and that it was “like a scene from a horror movie”.

Multiple people reported seeing several young children bleeding in the road after being stabbed.

Photos from the scene after the attack showed a police cordon on the street as well as large numbers of emergency service vehicles and personnel.

Forensic workers could also be seen in white hazmat suits.

Tim Johnson, a journalist with Eye on Southport, arrived about 20 minutes after the police had been called and said he saw one young girl on a stretcher.

“Her parents were running after her. It was horrendous. I’ve never seen anything like it,” he told the BBC.

“I saw ambulance men and women in tears. People were in tears in the streets.”

Ryan Carney, who lives on the street with his mother, said she was at home when she heard screaming and crying on the street.

She went outside to see a woman being allowed through the cordon by police as she tried to find her child.

One local parent who did not want to be named said his daughter had been present at the attack but had managed to run away.

He said she was safe but had been left “traumatised”.

Therapy nurse Joanne Newman, who lives in the area, said she had run out of work after hearing about the incident from a friend.

She said her daughters had not been harmed in the attack but that one had heard a “sinister scream” around the time of the attack.

“Nobody can believe it. All the local mums have checked in with one another,” she said.

She added that she had been consoling the mothers of one of the children who had been injured.

“How do you even comprehend? There’s nothing you can do,” she said.