POLICE are appealing for witnesses to a car crash which led to a have-a-go-hero being threatened with a knife to come forward.

Officers have released descriptions of two men they want to question following the smash on Halliwell Road yesterday afternoon involving an Audi A3 and a white van.

The driver of the Audi fled the scene before being detained by a member of the public nearby on Rushey Fold Lane.

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A short time later a second man, driving a silver Seat Ibiza, arrived on the scene and threatened the man ­— who had rushed from a nearby pub to give chase ­— with a knife before allowing the Audi driver to get in the parked Seat, which was driven off.

The driver of the Audi A3 is described as Asian, aged between 19 – 24-years-old, around 6ft tall and of slim build with short dark hair. He was clean shaven and wearing a red puffer jacket with black jeans.

The driver of the Seat Ibiza is described as mixed race, aged 20-25-years-old and had a scar under his right eye.

In a statement police said: "Investigators are appealing for information and want to speak to anyone who saw the incident take place or the cars in the area before the collision.

"Officers are particularly keen to speak to any members of the public who may have dash cam footage and are urging people who were in the area to check their dash cams to see if any of the incidents were captured.

"Details can be passed on to police by calling 0161 856 5508 quoting incident number 0875 of 01/04/19.

"Alternatively, information can be given anonymously to the independent charity Crimestoppers on 0800 555 111."