England has reported the death of two children and injury of nine others - six critically - in a stabbing at a dance class in Southport, near Liverpool in northwest England, on Monday. 

Merseyside Police announced at a press conference that a 17-year-old male has been arrested on suspicion of murder and attempted murder in connection with the incident. The attack also critically injured two adults.

Although counterterrorism police had volunteered to aid, according to police chief Serena Kennedy, the attack was not being investigated as a possible act of terrorism and its motive was not immediately apparent.

She also said that every injured person had been stabbed.

Prime Minister Keir Starmer expressed to the media that "the events today are just truly awful, the whole country is deeply shocked... Our thoughts and condolences are with the victims, families, friends and wider community. It is almost impossible to imagine the grief."

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Chief Kennedy relayed that just before midday (1100 GMT), police were summoned to a property where small children were taking a dance lesson in a Taylor Swift theme. 

Officers were "shocked to find that multiple people, many of whom were children, had been subjected to a ferocious attack," she added, noting that the suspect entered the room from the street and began attacking the kids, despite the adults there trying to shield them.

After detaining the man, armed police confiscated a knife.

Kennedy said, "As a mum and nana, I can't begin to imagine the pain and suffering that the families of the victims are going through."

Eleven victims with stab wounds were treated at the scene by the North West Ambulance Service (NWAS), and they were then transported by ambulance and helicopter to Alder Hey Children's Hospital and other nearby hospitals.

Alder Hey Children's Hospital stated, "We can confirm that the trust has declared a major incident."

One of the people who reported the incident to the police was local business owner Colin Parry, who told the Press Association news agency that he believed multiple "young girls" had been stabbed.

Local business owner Bare Varathan told the PA that he witnessed "seven to ten kids" who were "injured, bleeding" and that he also noticed that they had been stabbed.

According to police, "Inquiries are ongoing to establish the motive for this tragic incident" while the suspect is in custody.

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An AFP reporter on the scene said several locals who were let to leave the police cordon that was enclosing the area were horrified.

An individual residing on a nearby street, who wished to remain anonymous, told AFP, "It's not what you expect to see in Southport."