Two foreign workers have been abducted by rebels following an attack on an oil field in Sudan. There is mixed reports about the nationality of one of the hostages -- identified by some media outlets as Canadian.

The Justice and Equality Movement (JEM), one of Darfur's strongest rebel groups, has confirmed it attacked the Defra oil field in the Kordofan region on Tuesday.

The group reportedly inflicted losses to the Sudanese army and abducted the workers.

Sudanese media is reporting that the rebels took a Canadian and an Iraqi national hostage.

However, the head of the JEM in the Kordofan region, Mohamed Bahr Hamdeen, told The Canadian Press that the hostages were one Iraqi and one Egyptian.

"I don't know if the Egyptian has dual nationality,'' Hamdeen said by telephone from Darfur.

Shaun Tinkler, a spokesperson for the Department of Foreign Affairs and International Trade, told CTV.ca that Canadian officials are "aware of media reports stating that a Canadian citizen has been kidnapped in Sudan."

"Officials from the embassy of Canada in Khartoum will follow up with local authorities in Sudan to obtain further information," he said.

Hamdeen told AP that the two workers were "in good health."

He said the JEM carried out the attack because the oil companies are indirectly funding Khartoum's war effort in Darfur.

"This military operation is a clear message to oil companies working in Kordofan: The staff, especially foreign workers, have been given a week, starting yesterday (Wednesday) to leave, or else the companies and its foreign staff will become a legitimate target for the movement,'' Hamdeen told AP from Darfur.

The oil field is run by a Chinese-led consortium and Hamdeen said the attack was a warning to China to stop supporting and funding the Sudanese regime.

"We consider them (all foreign oil companies) as killers because they help the government buy the weapons which they use to kill women and children,'' said Hamdeen.

Meanwhile, the Sudanese military confirmed that the attack had taken place but denied that the rebels had made any impact on the country's 500,000 barrel per day oil output.

"It was insignificant,'' a Sudanese army spokesman told AP. "From a military point of view, they have done nothing.''

Sudan's turbulent Darfur region has been the focus of international concern since 2003, when ethnic African rebels began fighting against the country's Arab-dominated central government.

The government is accused of retaliating with the brutal janjaweed militias, blamed for terrible atrocities against Darfur's rebels.

The conflict has displaced more than 2.5 million people and more than 200,000 have died.

With files from The Associated Press