A 15-year-old boy has been stabbed to death in east London.
Police said they were called at 16:05 BST on Tuesday to Stoke Newington in the borough of Hackney, where they found a teenage boy with stab wounds.
He was pronounced dead at the scene on Stellman Close.
The suspect ran away and the Metropolitan Police says it is “working hard” to identify them.
Officers have appealed for anyone with any information to get in touch.
“We know this happened in a busy area during the day and there would have been people around,” said Det Ch Insp Kelly Allen, who is leading the investigation.
“The suspect is believed to have run away from the scene and I would appeal to anyone who saw anything suspicious in the Stellman Close area around 4pm to contact police.”
Det Ch Supt James Conway added: “The death of a child is devastating and my first thoughts are with his family and friends.”
He added: “Our communities will also be deeply concerned by this event.
“Urgent inquiries are under way and my officers are working hard to identify the suspects.
“Local residents can expect to see a notable police presence in the area as the investigation continues and there will be road closures in the Stellman Close area for some time.”
One resident described the area as a close-knit community.
Mayor of London Sadiq Khan called the killing “devastating news”.
“My thoughts and prayers are with his loved ones and all those affected by this tragic loss,” he said.
“Violence of this kind has no place in our society. There is no honour in staying silent – I urge anyone with any information to come forward as soon as possible.”
He added: “An urgent investigation into what happened is already under way, and I have been in close contact with the Met Police since yesterday evening, who will be providing an update on their investigation later today.”
He said the Met was also “increasing patrols in the local area”.