More than 20 Chinese nationals have gone missing after an attack by rebels against a camp belonging to a Chinese company operating at Sudan's South Kordofan area, the Chinese Embassy in Khartoum confirmed Sunday.

"The Chinese embassy has started implementation of the emergency mechanism to follow up the issue and make contacts with the Sudanese authorities in this respect," an official at the Chinese embassy told Xinhua.

Meanwhile, a spokesman of Sudan People's Liberation Movement's (SPLA) northern sector on Sunday said the movement was holding 29 Chinese nationals working for a Chinese company operating in the field of roads at South Kordofan state which has been recently witnessing armed clashes.

"Armed clashes took place between our forces and the Sudanese army at an area near Al-Abbasiya Tagali town in South Kordofan. We have controlled the area and 29 Chinese were held," SPLA spokesman Arno Taloudy told Xinhua by phone from the Kenyan capital of Nairobi.

"The Chinese workers have been transported to a safe area and they are in good health and in safe hands," he added.

South Kordofan state Governor Ahmed Haroun on Saturday announced that an armed group belonging to Sudan People's Liberation Army had attacked earlier in the day a site of a Chinese company operating in the state.

The official SUNA news agency quoted Haroun as saying that a group of rebels launched an attack on the site of the Chinese company on the circular road between Al-Abbasiya and Rashad localities near al-Mugarah area.

The governor said that the armed forces have immediately and firmly dealt with the situation, noting that the situation needs a high level of wisdom so that none of the 35 people working in the company, most of them Chinese, would be affected.

South Kordofan on the border between Sudan and South Sudan has been witnessing armed clashes between the Sudanese army and the SPLA's northern sector since June of last year.

Khartoum earlier ordered the SPLA forces to leave all the areas within north Sudan territories or disarm the movement's fighters if they wanted to stay in the north.

Khartoum accuses South Sudan of supporting the rebellion which is active on the borderline between the north and the south, particularly Blue Nile and South Kordofan areas.