The victim of a hit-and-run in Christchurch early has died, police have advised.

The victim, Steffan Pearce-Loe, aged 30, of Christchurch, died overnight on Thursday, July 5.

Pearce-Loe was hit by a vehicle while taking his dogs for a walk near his home in Dallington at around 2.30am on Thursday morning.

He had left his Dallington home and was located on the north side of the Gayhurst Rd bridge in a critical condition.

His two dogs were found nearby unharmed.

Detective Senior Sergeant Greg Cottam said police are continuing to examine CCTV footage in the area, and are working to identify broken car parts left at the scene.

"There may be a number of reasons for the driver not coming forward but we urge them to do so, so Mr Pearce-Loe's family can have some answers.

"We would again ask anyone who saw the victim walking two dogs in the Dallington area around midnight, or who knows how he sustained his critical injuries, to please get in touch with us."

Anyone with information is asked to contact Acting Detective Sergeant Ben Rolton of Christchurch Police on 03 363 7400, or Crimestoppers anonymously on 0800 555 111.