A teenager appeared in court Thursday charged with murdering three girls in a mass stabbing at a Taylor Swift-themed dance party as violent protests over the attack erupted in several English cities.
The 17-year-old -- who cannot be named due to his age -- faces three counts of murder and 10 of attempted murder following the killings Monday in Southport, northwest England.
The attack has shocked the country, while misinformation online about the background of the suspect has fuelled violent disturbances by far-right agitators who targeted a mosque and clashed with police in Southport.
Protests rocked London, and the northern cities of Hartlepool and Manchester on Wednesday night. More than 100 people were arrested outside Prime Minister Keir Starmer's official Downing Street residence.
Starmer was to hold an emergency meeting Thursday with police chiefs seeking to quell the unrest.
The stabbing suspect was remanded in custody during a five-minute appearance at Liverpool magistrate's court. He was to appear at the city's Crown Court later in the day.
The youth wore a baggy grey tracksuit and black slippers and smiled before he was asked to sit down, according to reporters in the courtroom.
A judge in the Crown Court was to give a further ruling on the youth's detention.
The teenager is accused of murdering Bebe King, six, Elsie Dot Stancombe, seven, and Alice Dasilva Aguiar, nine.
He allegedly wounded another eight children and two adults during the frenzied attack that has sparked an outpouring of grief in Southport, a quiet seaside town.
Social media misinformation about him contributed to violent clashes in Southport on Tuesday night, in which bricks were thrown at a mosque and 53 police officers were injured.
Police have blamed members of the far-right English Defence League grouping, an Islamophobic organisation founded 15 years ago whose supporters have been linked to football hooliganism.
The protests spread on Wednesday, including to Downing Street.
Protesters throw bottles at police and shouted, "We want our country back" and "Stop the boats," -- the latter a reference to small boats bringing irregular migrants across the Channel.
In Hartlepool, northeast England, demonstrators set police cars on fire and threw objects at the officers, with police saying eight arrests were made.
Hartlepool police said officers faced having "missiles, glass bottles and eggs being thrown at them, with several suffering minor injuries."
At the meeting with police leaders, Starmer will say the events at Southport "serve as a reminder of the bravery of our emergency service workers and the vitally important work they do to keep the public safe," a statement by the prime minister's office said.
He will also say that while the right to protest must be protected, "criminals who exploit that right in order to sow hatred and carry out violent acts will face the full force of the law".
The Labour government has vowed to clampdown on crime and antisocial behaviour, with interior minister Yvette Cooper promising policies including ramping up the presence of community police "in every corner of the country".
Starmer will tell police leaders "that they should not hesitate to use their powers to stop mindless violence in its tracks and make sure justice is served," the statement said.
