They concluded that the signs of life they had detected earlier were false.

Hopes had been raised that someone might have survived under the rubble for 15 days - since the earthquake measuring 7.4 on the Richter scale devastated north-west Turkey.

It is known to have killed at least 14,000 people, many of them crushed as they slept in their apartment blocks. Thousands more are missing.

A US rescue team had joined the search

Sniffer dogs had detected signs of life in the remains of the five-storey building in the seaside town of Golcuk on Wednesday.

But after hours of searching and rumours that the survivor had used a mobile phone to alert authorities, the rescuers' listening devices turned up nothing.

Earlier a man had phoned Interstar Television to say the mobile phone number broadcast as the survivor's was his, and that he was on holiday elsewhere in Turkey.

The last survivor found was a toddler, who emerged from the remains of a building on 23 August.

Hole drilled in rubble

Dr Izzet Erdogan, on stand-by at the site, had said there was "a chance in a million" of finding anyone alive after such a long time.

"If there is a survivor, it will be a world record," he said.

Turkish and US rescue teams had tried to reach the basement floor using a jack-hammer to drill a hole through the rubble and twisted metal.

Most of the international search-and-rescue teams left Turkey last week, after giving up hope of finding anyone alive.

Parliament criticised

In another development, the Turkish president, Suleyman Demirel, has come under fire for vetoing an amnesty law at a time when attention is focused on dealing with the aftermath of the earthquake.

The controversial law would have released more than 20,000 prisoners from the country's overcrowded jails.

The law, which was passed by Parliament on Saturday, prompted a public outcry.