Khartoum - Unknown armed men have abducted four Chinese workers in Sudan's troubled Darfur region, the state news agency SUNA said on Sunday.

The assailants abducted the Chinese nationals - one engineer and three drivers - together with five Sudanese colleagues late on Saturday near Al-Fasher in North Darfur, SUNA said, adding that all had been working for a Chinese road company.

Authorities were chasing the attackers with 18 military vehicles, SUNA said, without giving further details.

Law and order has collapsed in most of the vast, arid Darfur region since mainly non-Arab tribes took up arms against the government in Khartoum, which they accuse of neglecting and marginalising them.

Gunmen often kidnap foreigners in Darfur to demand a ransom for their release.

In January 2012, rebels in Sudan's main oil-producing state of South Kordofan kidnapped 29 Chinese workers. They were released almost two weeks later. - Reuters