Christchurch police are hunting an offender following a serious assault in Bexley.

A police spokesperson said a man was critically injured on Pages Road.

The incident happened between Portchester and Farnborough streets. 

Police are focusing their investigation at the entranceway of Bexley Reserve, a popular spot for dog walkers.

“Police responded at 6.20am and are currently searching for the offender” the police spokesperson said.

“This is a relatively busy road, and it’s possible someone witnessed this event or captured it on dashcam.”

Police are asking anyone who saw the incident or has information that may assist the investigation to call 111 and reference the event number P052595811.

Neighbours near the scene said they didn’t see or hear anything suspicious.

All traffic has been diverted, including the local bus.