Report by ITV Wales correspondent Dean Thomas-Welch
The police watchdog will send investigators to assess whether it will carry out an independent probe into a crash in Cardiff which killed two teenage boys and sparked a riot.
Kyrees Sullivan, 16, and Harvey Evans, 15, were killed in the Ely area on Monday while riding an electric bike.
Chief Superintendent of South Wales Police Martyn Stone told a press conference in Cardiff on Tuesday that a "mandatory referral" had been made to the Independent Office for Police Conduct (IOPC) following the disorder to "ensure the matter receives independent scrutiny".
A spokesperson from the watchdog said: "We have been contacted this afternoon by South Wales Police to make a referral regarding the circumstances leading up to the fatal collision in Ely yesterday (Monday).
"We will be sending investigators to a police post incident procedure to begin gathering information and to assess whether the IOPC will carry out an independent investigation.
Mr Stone said the force had received CCTV footage that shows a police vehicle following a bike ahead of the collision, but insisted that there were no police vehicles on Snowden Road when the crash occurred.
His statement followed the footage emerging online after South Wales Police said the crash happened before officers attended the scene.
CCTV appearing to show a police van following a bike ahead of a fatal collision
“We can confirm the following investigations have been carried out so far and when the collision occurred there were no police vehicles on Snowden Road.
“A police vehicle on Grand Avenue responded to the collision, attended the area and officers performed CPR.”
Kyrees Sullivan, 16, and 15-year-old Harvey Evans were killed in the Ely area of Cardiff on Monday evening while riding an electric bike.
CCTV footage time-stamped to 5:59pm on Monday appears to show a police van following two people on a bike.
ITV News understands it is that video which caused tensions to rise following the crash and sparked the unrest.
Chief Superintendent Martyn Stone speaking at a conference on Tuesday evening
It comes after South Wales Police earlier denied a police chase took place.
Earlier today the force said it was aware of a video circulating on social media of a bike being followed by what appears to be a police van.
They said the collision had already occurred when officers arrived, and they remained on the scene to manage "large-scale disorder" until the early hours of Tuesday morning.
Tensions reached breaking point after officers were called to the scene in Snowden Road shortly after 6pm on Monday.
A large crowd of people gathered, many wearing balaclavas and face masks, and were seen throwing objects at police and their vehicles.
Kevin Brennan, MP for Cardiff West, said there is 'an overwhelming feeling of sadness' in the community.
"This is a terrible tragedy, two young lives have been lost. There are families and friends grieving and I know the overwhelming feeling of people here is of sadness.” He said.
Mr Brennan also said he believes there has to be "a proper independent investigation into the events that led up to the incident as well as to the events that happened afterwards".
He continued: "Clearly the messaging we got today wasn’t clear about the fact that it’s clear there was some kind of interaction between the police van and the bikes involved and we need to get to the bottom of that with an independent investigation.”
When asked his thoughts on how the police handles the situation, Mr Brennan said he will not criticise the police, but said he believes they need to be “absolutely clear, open and transparent about what happened because people do need to know the truth and they deserve to know the truth of the events that took place.”
Mr Stone confirmed while speaking to the press that 15 police officers needed medical attention following the disorder.
He also confirmed that a referral has been made to the Independent Office for Police Conduct (IOPC) following the disorder in Ely and said more arrests will be made.
He said: “I would like to acknowledge the impact last night’s disorder had on local residents, who are understandably very frightened.
“They have our assurances that we will be doing our best to arrest all of those responsible. A number of arrests have already been made and more will follow.
“We’re extremely grateful for the support shown by the local community and urge anyone with information to contact South Wales Police.
“South Wales Police has also made a mandatory referral to the Independent Office for Police Conduct to ensure the matter receives independent scrutiny.”
The South Wales force said arrests have been made but did not say how many.
The Independent Office for Police Conduct have since confirmed it will send investigators to start “gathering information and to assess whether the IOPC will carry out an independent investigation”.
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