Key Points:

An "uncouth" fugitive remained on the run today after sparking a full-day manhunt across south Canterbury yesterday.

At the height of the drama, police from Timaru, Geraldine, Temuka, Ashburton, Methven and Christchurch were searching for the man.

They gave up about 4pm, hours after he abandoned the ute he was driving and fled on foot into scrub alongside the Rangitata River.

The drama began about 9am in Mt Somers, when the man failed to stop for police.

Backup from surrounding areas, including the armed offenders squad and dog units from Christchurch, was then called in to help.

Roads were cordoned off and traffic slowed on the Rangitata bridge before the area eventually went into lockdown.

Police described him as an "uncouth" man, in his late 20s or early 30s, of medium build, with "long, straggly, oily, stringy hair".

He wore green clothing, and a jacket similar to the non-camouflage army kind.

Ashburton Senior Sergeant Grant Russell said the man was not believed to have a weapon but if people saw him they should keep their distance and call police.