A HUNT is on for a motorist who crashed into a motorcyclist on a Hampshire motorway and then sped off without stopping, leaving the rider lying seriously injured in the carriageway.

Detectives hunting the driver say he had already been spotted driving dangerously and erratically along the M271 in Southampton before the accident happened on Thursday.

As he careered along the motorway in an old-style M-Reg Ford Escort, he was seen swerving between lanes before suddenly colliding with the motorbike.

The collision forced the bike into the back of a Nissan, with the bike and rider then bouncing off the Nissan into two other cars - a Vauxhall Astra and a Ford Escort - before it came to a rest.

During the crash the rider was thrown from his bike and suffered what police described as serious though not life-threatening injuries.

The dark blue Ford Escort being driven by the man being hunted then failed to stop at the scene.

Police say they believe his car will have suffered some bodywork damage during the accident to its nearside and are appealing for anyone who can help trace the driver to get in touch.

Anyone with information is asked to contact the Roads Policing Unit on 0845 045 45 45 or Crimestoppers anonymously on 0800 555 111.