The international relief operation to help survivors of the earthquake in Turkey is now in full swing.

Millions of dollars worth of aid has been pledged, planeloads of tents and medicines are arriving and international rescue teams with sophisticated equipment are helping to search for survivors.

They are facing huge problems, including blocked roads and damaged electricity and telephone systems.

Experts say past experience has shown that the early stages of the operation could also be hampered by other logistical problems.

"Unfortunately the management of major natural disasters like these in the past does have many instances of rather chaotic management, especially in the first few days," said Mike Evans of Cranfield University's disaster management centre.

Equipment delay

"Things like the arrival of specialist search equipment can be delayed at ports of entry for customs clearance.

"There's also the provision of liaison officers to specialist teams and their allocation to search areas. One of the major problems is to keep track of which areas have been searched and which haven't."

A young girl is rescued from the rubble in Istanbul

One of the main challenges facing the Turkish authorities is how to co-ordinate this huge influx of aid and rescue teams, while continuing their own search and rescue operations and battling a huge refinery fire set off by the earthquake.

Abdullah Demirkol, a Turkish doctor who arrived in the city of Izmit shortly after the disaster said that, while the authorities were trying their best, there was virtually no co-ordination between various government agencies.

None of the Turkish public services were working in a co-ordinated manner because Turkey had no preparation for disaster relief, he said.

At the moment, there were about 575 crisis centres, but the food centre had barely any contact with the health desk or the health desk with security, he added.

Complaints expected

Turkey's Health Minister, Osman Durmus, admitted there were problems during the early stages of the operation. But he said things were getting better.

"Of course there are complaints. Everyone wants to be saved at once - and of course they're right," he said.

"For example, you can start rescue operations in 50 areas - but in another 50 areas where there are no operations, people are crying for help.

"We've asked for equipment from the private sector and from the Istanbul authorities. There are also international teams coming in. I think it will be possible to have the rescue operation at full capacity by Thursday."

International teams currently arriving in Turkey are bringing with them sniffer dogs, and high tech equipment which can detect people buried under rubble through sound or body heat.

Survival rates dropping

Turkey will have to provide special liaison officers with language skills to co-ordinate their work But even if all goes well, the chances of rescuing survivors alive are becoming increasingly slim.

"Unfortunately survival rates are now dropping off markedly," said Mr Evans.

"Half of live rescues are conducted in the first six hours after the impact of an earthquake. Even after six hours, around 50% or less of the trapped people are still alive.

"But we're now getting into the third day after the disaster. I wouldn't like to quote hard percentages, but I think we're now into the area of under 20%."

Much may depend on how effectively the Turkish authorities can co-ordinate the relief effort.