A teenage boy has been killed after answering his front door in the London town of Croydon.
Police believe the killer or killers knocked on the boy's door in Bracken Avenue at about 12.46am on Thursday morning (local time), and attacked with a knife when the door was opened.
Officers found the teenager inside with stab wounds.
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They provided first aid, but the boy was pronounced dead at the scene.
The boy has not yet been formally identified, but police said his next of kin had been told of his death.
Police are also investigating a second, linked crime scene nearby where a car believed to be used by the suspects had been dumped.
Chief Superintendent Andy Brittain, in charge of policing in Croydon, said the family was being supported.
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"I am deeply saddened by the needless loss of yet another young life to knife crime," he said.
"The full circumstances surrounding this incident are yet to be established, but even at this early stage I do know, that this young man being killed inside his family home, will send shockwaves through our community."
Nobody has been arrested, and the investigation continues.
