An 18-year-old man has been arrested on suspicion of murdering Leonne Weeks, 16, who was found dead on a path in Rotherham.
Rave Death Investigation
An investigation's underway into why police didn't do anything to stop an illegal rave in Croydon where a 15 year old boy fell ill.
Rio Andrew died in hospital on Monday 16 June 2014. The Met Police say they had intelligence suggesting a rave might take place - more than a week before it happened on the night of Saturday 14 June.
Rio Andrew's school say he was "destined for academic success".
He was among 2,000 revellers who descended on a disused sorting office in Cherry Orchard Road, Croydon, in the early hours of Sunday.
The teenager is understood to have drunk from a bottle of beer believed to contain the illegal party drug ketamine, the Croydon Advertiser reported.
He was taken from the venue by ambulance to hospital, where he died.
Scotland Yard said the cause of death has still to be confirmed and a post-mortem examination is being arranged.
Borough Commander Simon Letchford confirmed that police believed Rio had an "adverse effect" to drugs taken shortly before his death.
He said: "We've got a number of lines of inquiry that we're following but we believe he's taken some sort of drug that's had an adverse effect on him.
"We want to identify who's provided that to him, where he's got it from and, if we can identify the individuals concerned, we'll look to prosecute them."
The force has launched an internal review after it emerged that officers received intelligence about the illegal rave two weeks before it took place but took no further action.
Tributes have been paid to Rio, from Notting Hill in London, who was described as "a much-respected student" and an "exceptional sportsman", especially in shot put.
The Year 10 pupil at Holland Park School in Kensington, west London, was chosen to be part of the Jamaican national team's guard of honour at the 2012 Olympics.
In a statement posted on its website, Holland Park School said students and staff "deeply regret this sad loss of a much- respected student".
"Rio was an able scholar, destined for academic success, " the school said.
"He was also an exceptional sportsman and due to be awarded this Friday a prestigious sports award.
"The school wishes to send its collective sympathies and respect to all of Rio's family and friends. He will be greatly missed by the school community."
Tributes flooded on to Twitter following his death.
One friend wrote: "Today I lost one of my closest friends, Rio Andrew. Words cannot even explain how heartbroken I am. Love you dude."
Another tweeted: "RIP Rio Andrew. You were so talented and amazing and it's such a shame. You were my mate since primary and it's heartbreaking to let you go."
One friend said: "Rio Andrew, 15, my best friend dead. It's times like this where we won't be scared but we look at the world from a different angle."
A 19-year-old man who became ill at the illegal rave after reportedly drinking from the same bottle is still in hospital in a stable condition.
Scotland Yard said it was aware of six other people who were taken to hospital. All six have been discharged.
The rave was spotted by officers on routine patrol who saw "large numbers of people inside, outside and heading towards" the disused building where music was being played on Saturday at around 9.40pm.
Violence broke out after police clamped down on the rave by trying to stop more revellers getting to the building.
Scotland Yard said a number of people in the crowd became violent, and missiles were thrown at officers. The window of a police vehicle was also smashed.
Officers continued to surround the venue until they raided it on Sunday at about 8.30am.
Fourteen people were arrested for a range of offences including drugs, violent disorder and money laundering.
Two men have been charged with violent disorder and drugs offences, and a 47-year-old man and a 30-year-old man were given adult cautions for possession of class A drugs.
Another three men were arrested on suspicion of money laundering, a 17-year-old boy was arrested on suspicion of violent disorder and a 22-year-old man was arrested on suspicion of criminal damage. All five have been bailed pending further inquiries.
Scotland Yard said another five men are still in custody after being arrested for handling stolen goods and criminal damage offences.
Mr Letchford admitted he would have expected "a bit more to have been done" after police were tipped off about the illegal rave two weeks beforehand.
Speaking outside the Scotland Yard headquarters, he said: "About two weeks before, we had a single piece of intelligence that suggested that there may be an event on at this venue. It was assessed at the time and no further action was taken.
"I've now asked for a review into the decision-making around that, why we didn't take any further action. I would have expected a bit more to have been done. I'll need to find out why that wasn't done at the time."
Mr Letchford said police allowed the rave to continue to avoid trouble spilling out on to nearby streets.
"Officers became aware a significant number of people had turned up at a disused venue in Croydon," he said.
"Unfortunately, a number of those people then became violent and started to attack officers, throwing fire extinguishers.
"We think we had 2,000 people in a potentially very volatile situation.
"The commanders on the ground made a very difficult decision to allow them into the premises and contain them into those premises, rather than allow them to go out into the streets and potentially cause significant damage to residential and business property."
He added: "These events are, by their very nature, criminal. We're going to do everything in our power to identify those responsible."
Mr Letchford said police were not aware of a particularly dangerous batch of drugs linked to Rio's death but stressed that anyone taking illegal substances is putting themselves at risk.
Police have appealed for anyone with information to contact Croydon CID on 020 3276 2264.
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