Greater Manchester Police (GMP) has referred itself to the police watchdog over the death of a teenager.
Rhamero West, 16, was stabbed to death after being chased through the streets in Old Trafford on 9 September.
A 16-year-old, who cannot be named for legal reasons, has been charged with his murder.
The force said the case had been "subject to a complaint" and was now being investigated by the Independent Office for Police Conduct (IOPC).
The IOPC confirmed it had received a referral from GMP "due to the fact officers had contact with a 16-year-old boy prior to his death".
"The referral is currently being assessed to determine what further action may be required from us," it said.
Catering student Rhamero, known as Mero, from south Manchester, died after being found on Norton Street at about 18:00 BST following his first day at college.
It followed "violent disorder" and several car crashes in Manchester, the force said.