"The team and the sniffer dogs are exhausted," Heinrich Ganss, spokesman for the volunteer organization Technisches Hilfswerk (THW), said Monday in the western city of Darmstadt.

Ganss said the Germans, who have been deployed since Saturday, were discouraged that they had been unable to recover further survivors from the rubble in the southeastern city of Bam while "corpses pile up on the roadsides".

The 30-strong recovery team is to return to Frankfurt and will be received by Interior Minister Otto Schily, Ganss said.

The interior ministry said in a statement that it would send eight additional THW experts to install water treatment systems, bringing the total of such experts in the country to 13.

"The federal government will intensively continue its aid work for the affected people in Iran," the ministry said.

"The THW will now shift the focus of its engagement and assist in providing drinking water."

A foreign ministry spokeswoman said that Germany had provided 33 tonnes of humanitarian aid to date at a value of 700,000 euros (875,000 dollars) and that the government was in talks with Iranian officials and international partners on providing further assistance.

At least 30,000 people are believed to have been killed in Friday's quake that registered 6.3 on the Richter scale and completely devasted the ancient fort city, according to the latest toll.

TERRA.WIRE