The German daily Die Welt newspaper, in an advance release of its Wednesday edition, citing unnamed western security sources, said that injuries apparently caused by chemical arms were found on the bodies of the victims.

It said that witnesses quoted by an Arabic news website called ILAF in an article on August 2 had said that several frozen bodies arrived suddenly at the "Al-Fashr Hospital" in the Sudanese capital Khartoum in June.

Die Welt said the sources had indicated that the weapons tests were undertaken following a military exercise between Syria and Sudan.

Syrian officers were reported to have met in May with Sudanese military leaders in a Khartoum suburb to discuss the possibility of improving cooperation between their armies.

According to Die Welt, the Syrians had suggested close cooperation on developing chemical weapons, and it was proposed that the arms be tested on the rebel SPLA, the Sudan People's Liberation Army, in the south.

But given that the rebels were involved in peace talks, the newspaper continued, the Sudanese government proposed testing the arms on people in Darfur.

Details of what were in the weapons were not disclosed.

The Sudanese government has been accused of arming and backing Arab militias, known as Janjaweed, which have rampaged through the western Darfur region for the past 19 months.

An estimated 50,000 people have been killed and 1.4 million more uprooted in a campaign against Darfur's black African population, which began in February 2003 when Khartoum and the Janjaweed cracked down on a rebel uprising.

The United States has accused Syria of trying to acquire materials and the know-how to develop chemical weapons and claims that Sudan has been seeking to improve its capability to produce them for many years.