A group of 29 Chinese workers taken by rebels in southern Sudan 11 days ago has been freed in good health and flown to Kenya, officials said on Tuesday, after Beijing protested their capture.

Insurgents from the Sudan People's Liberation Movement-North (SPLM-N) confirmed the release of the Chinese, who initially spent two or three days walking away from the "front line" in a war zone through sometimes difficult terrain in the Nuba Mountains after their capture, a rebel spokesman told AFP.

The International Committee of the Red Cross said it arranged the transport of the 29 Chinese to Kenya on an ICRC aircraft.

"The Sudanese authorities allowed a Red Cross plane to take them from Kauda to Nairobi... this Tuesday morning where they were given to the Chinese embassy there," Sudan's foreign ministry said.

Rebels say they control Kauda town in South Kordofan state, where they have since June been fighting with government troops.

China last week lodged a formal protest with Khartoum over the workers' capture and dispatched a six-member team to help gain their freedom.

Vice Foreign Minister Xie Hangsheng summoned a top-level Sudanese embassy diplomat and urged the African nation to "do everything it can to ensure the safety of the Chinese personnel," the ministry's website said.

Late Tuesday the ministry confirmed the workers had arrived in the Kenyan capital, the official Xinhua news agency reported.

"The 29 persons are currently in sound physical conditions and stable mood," the ministry said in a statement quoted by Xinhua.

It added the workers were handed over to the Chinese embassy after they landed in Nairobi, where they appeared flanked by ambassador to Kenya Liu Guangyuan and Qiu Xuejun, head of the team sent to help secure their release.

They were due to head home after a short stay in Nairobi, Xinhua said.

"We were told that one of the workers had a problem with his leg" because of the initial walking after their capture, rebel spokesman Arnu Ngutulu Lodi told AFP. They were later moved by car, he said.

The captives, who were involved in a road-building project in South Kordofan, had been held since January 28 when the SPLM-N destroyed a Sudanese military convoy between Rashad town and Al-Abbasiya and took over the area, the rebels said.

ICRC said it was not involved in negotiations to free the Chinese.

According to Xinhua the workers were taken after a rebel attack on their camp.

Sudan's foreign ministry spokesman Al-Obeid Meruh said that in addition to the 29 freed Chinese, 17 others had earlier been "released" by the Sudan Armed Forces but one other Chinese died.

"His body was found yesterday," Meruh said.

Lodi said he did not know about that.

Chinese embassy officials in Khartoum could not be reached on Tuesday.

Lodi said discussions about the Chinese workers began last week when SPLM-N chairman Malik Agar met a Chinese diplomat and asked Beijing to use its influence with Khartoum to help badly needed aid to reach the war zone.

Agar's talks, in Addis Ababa with the Chinese ambassador to Ethiopia, were followed by more negotiations in Kenya, Lodi said.

He added the rebels did not set any pre-conditions for the workers' "evacuation".

"From the beginning we were saying they were not hostages" -- a term used by Sudan's military.

China is Sudan's major trading partner, the largest buyer of Sudanese oil and a key military supplier to the Khartoum regime.

Along with the 29 Chinese, the rebels say they captured seven suspected Sudanese national security agents, one of whom later fled.

"We are now also ready to release the remaining six," Lodi said.

Sudan has severely restricted the work of foreign relief agencies in South Kordofan and nearby Blue Nile state, where a similar war began in September.

About 30,000 people fled when the rebels took control of villages in the Al-Abbasiya area on January 28, the United Nations said.

The UN has backed statements by the United States that there could be a famine unless urgent aid is allowed to enter South Kordofan and Blue Nile.

burs-it/hkb