China's Foreign Ministry said on Tuesday it was "highly concerned" that suspected Boko Haram rebels from Nigeria had abducted Chinese workers in northern Cameroon, and urged authorities there to step up protection for its citizens.

In the attack on a Chinese work site in northern Cameroon, the rebels killed at least one Cameroonian soldier while 10 Chinese workers were missing and believed to have been abducted, officials and state media said. "We are maintaining close communication with Cameroon and other relevant governments and request that the relevant countries carry out the rescue efforts of Chinese businesses," China's Foreign Ministry spokesman, Hong Lei, told a daily news briefing.

"We also request that the relevant country's government earnestly safeguard the safety of Chinese personnel in the area and increase their protection." The Chinese embassy in Yaounde confirmed the attack on Friday at a site near the town of Waza, 20 km (12 miles) from the Nigerian border close to the Sambisa forest, a Boko Haram stronghold.

Chinese Embassy political counsellor Lu Qingjiang said one Chinese worker was injured in the attack and 10 were missing, China's state news agency Xinhua reported on Sunday.

Ten vehicles belonging to China's state-run construction company Sinohydro, which is repairing roads in Cameroon, were also taken in the attack, Xinhua said.

It quoted a company official, Lan Ronghe, as saying the injured man had been shot twice, in the shoulder and the abdomen, in the attack on his camp near the Waza park.

At least two Chinese enterprises operate in the region. Xinhua said a Sinohydro engineering unit ran the camp.

Yan Chang Logone Development Holding Company, a subsidiary of China's Yanchang Petroleum, is exploring nearby for oil.

Nigerian authorities say Cameroon has not done enough to secure its border because Boko Haram has been using the sparsely populated far north region as a transit route for weapons and as a base for attacks in northeastern Nigeria. Cameroon said in March it would send 700 soldiers to the border as part of regional efforts to tackle the armed group.