The video appears to show the police van turning onto Howell Road while Harvey Evans and Kyrees Sullivan continue toward Snowden Road, where the crash happened
CCTV has emerged that appears to show the final moments police followed Kyrees Sullivan, 16, and Harvey Evans, 15, around a minute before the crash in which they lost their lives.
In the footage, the two teenagers can be seen on an electric bike heading down Stanway Road in the direction of Snowden Road.
Violence erupted in the community following claims police chased the teenagers before they crashed, with an independent investigation being launched by the watchdog.
In the latest CCTV footage, a police van is seen travelling in the same direction on Stanway Road, about 16 seconds behind the bike.
The van then turns left onto Howell Road, while the bike continued travelling straight.
A timeline of events was set out by South Wales Police on Wednesday. Deputy Chief Constable Rachel Bacon said shortly after 18:01:18, the police vehicle travelled through Stanway Road and Howell Road.
At the bottom of Howell Road, it turned onto Grand Avenue at 18:02:31.
Police estimate the collision occurred on Snowden Road between 18:02:18 and 18:02:41.
The families of both boys released statements with Harvey's family saying "Our hearts are truly broken by the sudden death of Harvey, our much-loved son, grandson, brother, nephew, friend, and boyfriend.
“He lived life to the full, he had a big heart and deep down he truly cared. He was a best friend to Kyrees, and our thoughts and prayers are with his family also.
“We ask for peace within the community and request that people leave the investigation to the police so we can get the answers we so desperately need to lay Harvey to rest.
Kyrees' family described him as a "loving, caring handsome young man".
They said in a statement: "A loving son to Belinda and Craig, little brother to Aleah and Jordan and a special uncle KyKy to Myra.
“He was loved so much by his grandparents and aunties and uncles and his many cousins.
“Him and Harvey along with Niall were best friends since they were young and went everywhere together, they both had so many friends and were very well liked doing many things together, having fun & laughs!!"
On Thursday the schools where Harvey and Kyrees were pupils also published tributes to the two teenagers. Harvey's school, Bryn y Deryn Carnegie Centre, described him as a "a popular member of our school community".
Meanwhile, Kyrees was a pupil at Greenhill school, which said he will be remembered for his "quick wit and ability to make those around him smile".
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