Rescuers believe Gary Davison (inset) could be lying in an area of the mountain

An earlier three-day hunt for Gary Davison, 44, from Slough, Berkshire, was called off last weekend.

Rescuers admitted on Saturday that they were now looking for a body.

The search in Glaslyn followed new information from a retired policeman about a possible sighting on the day Mr Davison disappeared.

Search co-ordinator Ian Henderson from Llanberis Mountain Rescue Team said a man resembling the hill walker was spotted by Llyn Glaslyn between 1500 and 1530 GMT on 2 January.

Complex area

A 30-strong party from the Llanberis, Ogwen and RAF Valley mountain rescue teams, helped by dogs, took part in the search but no trace was found.

"It's not a huge area but it's a very complex area topographically. There are lots of crags, steep bracken areas and streams where Mr Davison could be lying," said Mr Henderson.

There was a concentrated ground search on Saturday

He admitted that there was "no optimism at this stage" for finding the draughtsman alive and that they were "looking for a body".

Rescue teams started from outside Vaynol Arms pub in Nant Peris.

Last week, a rucksack was found in the area where Mr Davison went missing although there was nothing inside linking it to the draughtsman, and two other rucksacks belonging to him had already been found.

The latest find has been sent off for DNA testing.

The alarm was initially raised for the walker on 4 January after friends found his car in Pen-y-Pass.

Up to 70 people, dogs and helicopters were then involved in the early exhaustive searches and another search was carried out last weekend.

Mr Davison was last spotted walking on his own towards either the Pyg Track or Miners' Track, which both lead up Snowdon.