A 15-year-old boy has died after being stabbed at a school in Sheffield, police have said.

He was injured at All Saints Catholic High School, in Granville Road in the city, at about 12:17 GMT.

Police and paramedics were called but the teenager died a short time later.

A 15-year-old boy has been arrested on suspicion of murder and remains in police custody, South Yorkshire Police said.

Assistant Chief Constable Lindsey Butterfield told a press conference the force was working “at pace to build a full picture of what had happened and how this tragedy unfolded”.

“We urge you to be mindful that there are loved ones at the centre of this,” she added.

A large police presence remained at the school and in the immediate area.

All Saints head teacher Sean Pender had sent a message to parents on 29 January about a lockdown at the site.

In it, he said the action was due to “threatening behaviour between a small number of students”.

ACC Butterfield was asked during the news conference about the reports but the officer said she could not share any information relating to it.

She concluded the press conference by urging people to avoid speculation and the sharing of content online “which could be distressing to them [the family] and detrimental to our investigation”.

A number of floral tributes and messages have been left outside the school this evening.

One of the messages described the teenager as someone who was “the life of a party” who “brought joy and laughter to everyone who knew him”.

It adds that his “bubbly personality was contagious”.

“I’ll never forget all the moments, all the laughs. You’ll be missed by so many,” it said.

A teenager who said he knew the 15-year-old also left a bunch of flowers outside the school.

The 17-year-old, who studies at a local college, heard the news through friends and said the boy who died was a fan of Sheffield United.

He said: “I’m a bit upset to be honest, it came as such a shock.

“He seemed quite a happy guy and a nice guy to be around.”

The school was last inspected by Ofsted in October 2023 and was rated as Good overall, with inspectors saying the school had a “strong ethos of warmth and respect”.

A number of parents had arrived at the school to collect their children earlier.

One told the BBC they were keen to get their youngster home after hearing a variety of rumours about what had happened, adding the “kids were getting panicked”.

According to the local newspaper The Star, the school’s head teacher sent a message to parents today.

He said it was with “shock and sorrow” that he had to tell people a pupil had been fatally stabbed.

He also said the school would be closed on Tuesday.

Amaan Ahmed, who manages the Castle Asian Community Trust near the school, said the area was no stranger to knife crime.

The organisation works with young people to help them stay away from knives.

He feared the boy’s death would leave parents wondering if they should send their children back to school.

“If it can happen in a public place like a school, people will be worried about going to the park I think too,” he added.

Asked about the incident while on a trip to Brussels, Prime Minister Sir Keir Starmer said his first thoughts “as a father” were with the victim’s family.

“The terrible stabbing in Sheffield is one where I think the whole country would want to reach out to the family, to the friends, to the school, the entire community in their grief and mourn with them,” he said.

Louise Haigh, the MP for Sheffield Heeley, said the news was “horrific” and her thoughts were with all affected.

“Serious questions will have to be answered about how this could have happened”, she said, adding she will work with the school, police and the council “to make sure they are”.

Education Secretary Bridget Phillipson said she was “devastated” by the boy’s death.

She added: “We are in contact with the school and council to offer support.”

In an emotional statement education minister Catherine McKinnell told the Commons: “My heart goes out to his family, friends and the entire school community at this very distressing time.”

South Yorkshire Mayor Oliver Coppard said he had spoken with Lauren Poultney, the county’s chief constable, and offered her his full support.

“This morning a teenage boy went to school like thousands of others across South Yorkshire but won’t come home; a young man who was a member of our community, with his whole life ahead of him,” he said.

Sheffield-based Anthony Olaseinde is an anti knife crime campaigner for the charity Always an Alternative and said the incident was “heart-breaking”.

“Something like this should not happen,” he said.

He said the charity had held sessions at All Saints and worked with young people at the school.

“I’ve been in the school mentoring with them,” he said.

“We did conflict management sessions. We made a short film raising awareness about knife crime with young people at the school.

“The young people were really engaged and positive.”

He called for better support and resources for organisations working with young people.

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