King Charles has condemned the Southport stabbings, which saw the death of two children and nine others injured, as "utterly horrific".
A 17-year-old boy from Banks in Lancashire remains in police custody following the stabbings - but the incident is not being treated as terror-related.
In a statement, the monarch said: "My wife and I have been profoundly shocked to hear of the utterly horrific incident in Southport today.
"We send our most heartfelt condolences, prayers and deepest sympathies to the families and loved ones of those who have so tragically lost their lives, and to all those affected by this appalling attack."
King Charles issued a statement
Getty/PASix of the children injured are in a critical condition. Two adults are also in critical condition, who police believe were "bravely trying to protect the children who were being attacked".
The children are understood to have been taking part in a sold-out Taylor Swift-themed class at a dance centre in the town when the attack was launched.
Officers were called to reports of a knife attack on Hart Street in Southport at 11.47am.
Chief Constable Kennedy said that when they arrived, they were "shocked to find" several children had been "subjected to a ferocious attack and had suffered serious injuries".
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A message from His Majesty The King following the tragic incident in Southport today. pic.twitter.com/4aUK8btptX
— The Royal Family (@RoyalFamily) July 29, 2024
Two adults are also in critical condition, who police believe were 'bravely trying to protect the children who were being attacked'
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Armed police officers then detained the 17-year-old and seized the knife.
Colin Parry, owner of Masters Vehicle Body Repairs, also on Hart Street, said earlier today he believed that six or seven "young girls" had been stabbed.
Another witness at the scene said he called police to an address behind the Hart Space studios, where a yoga class for children in school years two to six - aged between six and 11 - was underway.
Merseyside's Police and Crime Commissioner Emily Spurrell said: "I am utterly shocked and devastated to hear about the truly appalling incident this morning in Southport.
"First and foremost, my heart goes out to the young victims, their families and all who knew and loved them. I cannot even imagine the untold pain and heartache they are facing. My thoughts are also with all those who suffered injuries and who have been affected by this harrowing incident.
Merseyside Police Chief Constable Serena Kennedy speaking to the media at Southport Community Fire Centre
PA
Officers were called to reports of a knife attack on Hart Street in Southport at 11.47am
PA
"To hear that innocent, defenceless children have been attacked during a Taylor Swift event at a dance school as they enjoyed the start of the school summer holidays is unthinkable and absolutely abhorrent.
"These young people had their whole lives ahead of them and it is hard to find the words to convey our deep sadness.
"Our region will be heartbroken that more young lives have been lost at the hands of violence and more have suffered serious injuries, and I share local people’s deep concern and anguish.
"Thanks to the efforts of police officers, an arrest was made quickly and there is no wider threat to the public."
Sir Keir Starmer said that he "can't imagine what the victim's families are going through" and thanked the emergency services for responding quickly.