Protesters who have been camping at the Solid Energy coal mine development on the West Coast say the company had no right to evict them.

The campsite, set up by the Save Happy Valley Coalition in Buller, was removed yesterday by police and contractors. It was one of the country's longest-running environmental occupations.

The state-owned coal miner has denied the public access to a 480ha area around a planned extension to the Stockton opencast mine. It said trespassers face arrest and prosecution.

Chief executive Don Elder said the campsite was cleared for the protest group's own safety.

Protest spokesman Graham Jury said the eviction would not change the group's continued opposition to the development.

"We can reoccupy, and we will do if we feel it is necessary to stop the mine going ahead," he told Radio New Zealand.

The campsite was on public land and Solid Energy therefore had no right to remove them, he said.