China has lodged an official complaint to Zambia over the arrest of 31 Chinese nationals, said Lin Songtian, director-general of the Department of African Affairs of Foreign Ministry, while meeting with Zambia's temporary ambassador to China.

The Chinese Foreign Ministry did not elaborate on the circumstances under which the Chinese nationals were arrested. However, Lin added that Zambian authorities had not followed correct law enforcement procedures in detaining those arrested.

Lin added that China has urged Zambia to release the detainees as soon as possible in order to maintain the friendly bilateral relationship and cooperation between the two countries. 

Zambia's temporary ambassador to China said that China's position and concerns are understandable, adding that the situation will be reported to the country's government immediately. 

The representative added that Zambia treasures the bilateral relationship between the two countries, and is willing to work with China closely to deal with the case properly.