KEY POINTS:
Searchers working in hot, trying conditions are yet to find any sign of missing deaf woman Emma Agnew.
About 44 police have been combing the semi-rural areas of Spencerville and Brooklands, about 16km north of Christchurch, following information obtained in their inquiry, but have so far found nothing of interest.
Ms Agnew was last heard from via text message on Thursday morning last week, and her red Mazda Familia car was found about 9.45pm that day in Christchurch's Bromley Park after being set alight.
Much of the search area is covered in bush and scrub, and with temperatures reaching into the mid-20s yesterday, it made for hot work.
"The terrain varies from open pine needles to thick areas of blackberry and broom and gorse," said police search and rescue co-ordinator Sergeant Peter Summerfield.
"You get tired and a bit drained. People are drinking copious amounts of water."
The police dive squad is expected to arrive today or tomorrow to search waterways in the area.
The nature of the search indicates police may now be looking for Ms Agnew's body, but her family are hanging on to the the slim hope she may still be alive.
Detective Inspector Tom Fitzgerald said police were continuing to talk to a number of people who had been in touch with Ms Agnew before her disappearance.
They included people who had contacted her about buying her car.
They had been told of possible sightings of Ms Agnew's car driving in the northern suburbs of Christchurch late on Thursday morning, but these were still to be confirmed.
"[The car] may have returned to Christchurch about midday or mid-afternoon."
It was possible the person or people who had set Ms Agnew's car alight had no part to play in her disappearance, and they were urged to come forward.
