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Police are investigating after a 12-year-old British girl was stabbed to death while taking in a Christmas light display in the U.K. city of Liverpool.
Merseyside Police said Ava White suffered “catastrophic injuries” and died Thursday, after being taken to hospital.
Four teenage boys, aged 13 to 15, have been taken into custody on suspicion of murder, police confirmed in a statement.
According to The Guardian, police are now tasked with combing through hundreds of hours of CCTV and camera phone footage to get a better understanding of the events that led to White’s death.
Police say White was attending a Christmas tree lighting event that takes place annually on Liverpool’s busy Church Street. Police believe the girl got involved in a verbal argument, which turned into a knife attack.
A group of boys were seen running away from the scene as members of the public tried to save White’s life.
“Their world has been torn apart and no parent should ever have to face that knock on the door from police officers to say that their child has died,” said Assistant Chief Const. Jon Roy.
Police are asking witnesses, or anyone with video footage from the event, to come forward.
“Ava’s death should be a reminder to us all about the part that we each have to play in eliminating violence against women and girls,” said Roy, highlighting that fact that the girl’s death occurred on White Ribbon Day — the first day of an annual campaign to raise awareness about violence against women and girls.
Liverpool mayor Steve Rotheram tweeted that he was “horrified” by the attack.
“I am angry today for Ava and her family, for the parents across the region worrying about their children’s safety, and angry that such a heinous act should take place here,” he shared Friday.
Dame Rachel de Souza, children’s commissioner for England, also shared her shock and sadness.
Assistant Chief Const. Ngaire Waine told BBC News that police are not looking for anyone else in connection with White’s death.
“It’s very sad for the city but it is even sadder for her family. Their lives are never going to be the same,” she said.
“This is a very, very rare event, so I hope that will reassure people.”