A 13-year-old boy suspected of stabbing two boys at a secondary school is a former pupil, police have confirmed.
Police believe the teenager, a British national, went into a first floor classroom at Kingsbury High School, in Brent, north-west London, before spraying a substance towards a pupil.
He was arrested after being seen at a mosque, officers added.
Chief Superintendent Helen Flanagan told reporters: "Having entered the school, he proceeded out to a first floor classroom.
"He entered the classroom, and we believe he sprayed a substance towards a pupil as he entered the door.
"The suspect has then attacked another pupil, a 13-year-old in that classroom, stabbing him, and then the suspect has left, running down the hallway of the school.
"As he is leaving, he then attacked another victim, a 12-year-old, stabbing him before running off and away from the school."
'A child had been seen at a mosque'
Counter-terror police have been leading the investigation into Tuesday's attack.
But Ms Flanagan also said they were not treating the incident as a terrorist incident.
She added that officers believe he does not have a connection to the mosque, and that it was coincidental he was in the area.
She added: "Police were called by a member of the public at approximately 4.50pm over concerns of a child that had been seen at a mosque in north west London.
"Officers attended shortly after and arrested a 13-year-old boy on suspicion of attempted murder, and he remains in custody.
"At this point we do not believe the suspect to have any particular connection to that mosque, and at this stage, we think that it may have been coincidental that he ended up in that area, and all of those at the mosque have been incredibly supportive of this investigation.
"At this time, the incident has not been declared a terrorist incident."
Two boys, aged 12 and 13, were taken to hospital in a serious condition after the incident.
Police and ambulance crews were called at around 12.40pm and police said the suspect, who had a weapon, was detained just after 6pm following a search.
In a letter to parents, the school's head teacher said it was a "deeply traumatic event for the whole school community". Home Secretary Shabana Mahmood described the attack as "shocking".
(c) Sky News 2026: Boy arrested over double stabbing at Kingsbury High School in London is former pupil, police
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