Two children have died and nine others are injured after a stabbing in Southport, north of Liverpool, this morning.
All of the nine children who were injured were stabbed and six are in a critical condition.
Two adults are also in a critical condition.
Merseyside Police Chief Constable Serena Kennedy said: “We believe that the adults who were injured were bravely trying to protect the children who were being attacked.”
Southport stabbings: Follow live updates
A 17-year-old boy from Banks in Lancashire, who is originally from Cardiff in Wales, has been arrested on suspicion of murder and attempted murder.
Police were called to reports of a knife attack at an address in Southport at 11:47am this morning.
Chief Constable Kennedy said that when officers arrived they were “shocked to find” several children had been “subjected to a ferocious attack and had suffered serious injuries”.
She added: “It is understood that the children were attending a Taylor Swift event at a dance school when the offender, armed with a knife, walked into the premises and started to attack the children inside.”
The chief constable said the suspect’s motive is unclear at this early stage but the investigation is not being treated as terror-related.
Sky News understands the stabbings took place at a community centre called Hart Space, often used for mother and baby classes, on Hart Street in the Merseyside town.
A poster shows a “Taylor Swift Yoga and Dance Workshop” aimed at children aged between primary school years two and six (7-11 years old) was taking place at the centre at the time of the attack.
Specialist officers are supporting the families of the children who were killed and those who were injured, Chief Constable Kennedy has said.
Dave Kitchin, head of service for the North West Ambulance Service in Cheshire and Merseyside, said paramedics encountered a “devastating scene” when they arrived.
He added that ambulances and air ambulances were used to take the 13 victims to Alder Hey Hospital, Manchester Children’s Hospital, Aintree hospital, Southport Formby hospital and Ormskirk hospital.
Merseyside Police declared a “major incident” after the stabbings and armed police seized a knife when they arrested the teenage suspect.
The force then urged the public to avoid the area – as one local businessman described the scene as like a “horror movie” and said “mothers were screaming” in the aftermath.
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