Police have said three vehicles failed to stop at the scene of a collision which closed a stretch of the A12.

The crash led to the closure of the road near Capel St Mary on Sunday afternoon.

Police were called to the scene, on the northbound carriageway, at about 1.35pm.

Investigators said a motorbike, being ridden northbound, was in collision with three other vehicles.

When the motorcycle then left the road, the other three vehicles immediately left the scene.

The male motorcyclist was conscious when emergency services arrived.

He was taken to Ipswich Hospital for treatment to head injuries.

Enquiries are on-going to locate the other three vehicles, said police.

One lane of the northbound A12 reopend shortly after 5pm, according Highways England.

The crash scene was clear following investigation work but caused long delays for motorists.

Diversions were put in place for northbound road users from Ardleigh to Wherstead.

Anyone who witnessed the collision, or was travelling in the area and may have dash-cam footage of the vehicles, is asked to contact the police headquarters roads policing team on 1010, quoting CAD number 207 of July 29.

Relevant dash-cam or mobile phone footage can be uploaded at suffolk.police.uk/contact-us/report-something/9-dashboard-camera-report-form.