Chris Upton, headteacher at the Tarleton Community Primary School, tells PEOPLE that Saffie Rose Roussos’ death “has come as a tremendous shock.”
“The thought that anyone could go out to a concert and not come home is heartbreaking,” Upton says in a statement.
He continues, “Saffie was simply a beautiful little girl in every aspect of the word. She was loved by everyone and her warmth and kindness will be remembered fondly. Saffie was quiet and unassuming with a creative flair.
The girl attended the show with her older sister Ashlee Bromwich and mother Lisa Roussos, according to The Telegraph. Ashlee and Lisa are in separate hospitals being treated for injuries, but friends posted appeals online hoping to find the missing child safe.
Saffie was the second victim of the attack publicly identified.
An 18-year-old college student, Georgina Callander, was the first victim identified.
The school released a statement mourning the teenager.
“Georgina was a lovely young student who was very popular with her peers and the staff and always made the most of the opportunities she had at the school,” the school said. “Our thoughts and prayers go out to Georgina’s family at this terrible time, and we think especially of her brothers Harry and Daniel who are also former students of the school.”
Chief Constable Ian Hopkins said the explosion occurred around 10:33 p.m. local time near the ticket office outside the arena. The attack was carried out by a lone suspect carrying a bomb, Hopkins said.
“The attacker, I can confirm, died at the arena. We believe the attacker was carrying an improvised explosive device, which he detonated, causing this atrocity,” Hopkins said.
He added, “We have been treating this as a terrorist incident and we believe, at this stage, the attack last night was conducted by one man. The priority is to establish whether he was acting alone or as part of a network.”
According to the SITE Intel Group, ISIS has claimed responsibility for the attack.
Numerous reports highlighted Grande’s largely young fan base, including children, teens and young adults in the crowd of about 21,000.
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Many parents have not seen or heard from their children and are using traditional and social media to try to track them down.
“Ariana is okay,” her rep said in a statement to PEOPLE. “We are further investigating what happened.”
British Prime Minister Teresa May says her thoughts are with victims and families after what is being treated by police “as an appalling terrorist attack.”