Some 500 Zambian mine workers have been sacked after rioting and attacking a Chinese manager.
China's investment in Zambia is controversial
Those sacked have three days to reapply for their jobs, while seven union officials have also been arrested.
The Chinese manager at the Chambishi copper smelter in northern Zambia was admitted to hospital after the assault.
China has become a major investor in Zambia's run-down copper sector but workers have complained of low wages and poor conditions.
"They have all been dismissed with immediate effect," company spokesman George Jambwa told the AFP news agency.
"We have given three days to those who want to be re-employed to write to us and give reasons why they should join our company."
Albert Mando, general secretary of the National Union of Mining and Allied Workers (Numaw) said he was "surprised" by the dismissal, adding that the union could not negotiate when its officials had been arrested.
The workers threw stones at the managers as they attempted to hold talks, on Tuesday before police were called in.
Several buildings were burned in the violence and a protester was injured.
The protest was sparked by rumours that members of the Chinese management team were about to go on holiday, which workers feared would delay negotiations to improve their conditions of service.
Last year, China's president cancelled a visit to Chambishi fearing protests.
A blast at the copper mine killed 50 people in 2005.
Chambishi smelter, which is under construction, is part of a huge multi-million dollar Chinese investment in the area.
In recent years, China has emerged as one of the biggest buyers of Zambian copper.
But correspondents say Chinese investment in mining and manufacturing has not been without controversy - with constant industrial disputes amidst allegations of poor working conditions.
In elections in 2006, opposition candidate Michael Sata ran on an anti-China ticket, calling for "Zambia for Zambians".