Industrial action is spreading over Solid Energy’s coal mines.

Rotowaro opencast mine employees in the Waikato began action early last week after talks collapsed.

Since then, workers across the company’s sites have increasingly joined stop work action. About 780 are now participating and the company is appealing the EMPU to lift the action.

Yesterday morning, 500 Stockton opencast mine workers were the latest to join in. On Wednesday last week, about 100 Huntly East underground mine workers took action in support and have not returned to work.