Croydon stabbing: 15-year-old girl killed on way to school - what we know
What's happening? A 15-year-old girl has been stabbed to death on her way to an independent girl's school in Croydon.
Eyewitnesses to the attack said passersby attempted to resuscitate the victim, whose name has not yet been released by authorities, following the stabbing at around 8.30am on Wednesday - but she was pronounced dead at the scene less than an hour later.
Police responded within minutes, arresting a 17-year-old boy who is believed to have been known to the schoolgirl just over an hour after the incident took place.
Speaking at a press conference following her death, Chief Superintendent Andy Brittain told reporters: "This is every parent's worst nightmare."
London mayor Sadiq Khan said in a statement: "I am absolutely heartbroken by the death of a 15-year-old girl in Croydon this morning. My thoughts and prayers are with this young girl’s family and friends and the whole community, at this unimaginably awful time."
Read more: Girl stabbed to death in Croydon school bus horror as police arrest teenager (The Independent)
Yahoo News rounds up what has been happening in the aftermath of the stabbing...
Eyewitness accounts
Eyewitnesses from the scene said the stabbing had taken place outside of a bus, with the driver and a passerby attempting to save the girl.
"I was on the bus before and came off and walked back down, I saw them resuscitating her," one witness, known as Bridget, told the BBC.
"The driver was holding her and a lady. The emergency services were already here when I walked back."
Another passerby said the girl's friends tried to rush to her aid as she was lying on the floor.
"I turned around and could see that someone was trying to resuscitate her," Michael Fyffe told Sky News.
"There were loads of people who had just come off the bus and then I think two of the girl's friends came out and they were trying to rush over towards the body.
"So myself and a few of the other people tried to hold her back and just say, 'Look let them try and help your friend', and she was just screaming, 'Is my friend dead? She's my best friend.'"
Read more: Croydon: Horror on school run as 15-year-old girl stabbed to death ‘with machete’ in south London (Evening Standard)