Two Chinese managers accused of shooting protesting workers at a coal mine in Zambia have been cleared after prosecutors decided to drop the case, their attorney said Monday.

"The state entered nolle prosequi on Friday and this means that my clients are free," lawyer George Chisanga told AFP.

Nolle prosequi, Latin for "we shall no longer prosecute", is a decision by prosecutors not to continue with a case, usually because of lack of evidence.

Chisanga said the move means his clients are free for the time being.

"The implication of a nolle prosequi is that the director of public prosecutions can call you back to court. But for now, we are free," he said.

Managers Xiao Li Shan and Wu Jiu Hua were arrested in October last year after allegedly shooting and wounding 11 miners who were protesting against poor working conditions at the Chinese-run Collum Coal Mine.

Police said the pair had fired shotguns indiscriminately in a bid to break up the protest.

The incident halted production at the mine and took a toll on relations between workers and Chinese employers in Zambia, where China has invested an estimated $6.1 billion (4.3 billion euros) since 2007, mainly in mining.