Two police officers are under investigation for their conduct prior to the death of two boys in an e-bike crash in Cardiff which led to rioting.
The Independent Office for Police Conduct (IOPC) said gross misconduct notices had been served on the driver and passenger seen in a police van behind the boys in the Ely area.
Kyrees Sullivan, 16, and Harvey Evans, 15, died in the crash on 22 May.
Notices don’t necessarily mean officers will face disciplinary proceedings.
The two officers have not been suspended, South Wales Police said.
The IOPC said its investigation focused on the nature of the police interaction with the two boys before the crash and the appropriateness of the officers’ decisions and actions.
In particular, the police watchdog said it was examining whether the officers in the police vehicle were pursuing the boys.
Cars were set alight and fireworks thrown at police as 100 to 150 people gathered in Ely on the night of the crash.
South Wales Police and Crime Commissioner Alun Michael initially insisted the two teenagers were not being chased by police before they died.
The force later confirmed its officers had been following the teenagers prior to their deaths.
The watchdog said investigators were reviewing hundreds of video footage clips and had reviewed initial accounts and body-worn video from police officers and staff.