Over 50 protesters have broken into Kingsnorth power plant to protest at plans for a new coal-fired station on the site

Greenpeace activists have broken into a power plant in Kent, which is being considered as a site for the first new coal-fired station to be built in 20 years.

The protesters, thought to number more than 50, are calling for the prime minister Gordon Brown to reject the plans for the Kingsnorth site. They aim to take the plant off the National Grid during today鈥檚 action.

A spokesperson for the plant鈥檚 owners, E.ON UK, said some of the protesters were inside the facility, but insisted operations were not affected and it was still running.

"There are some in the power station, but just because they're inside that doesn't mean we have to shut down as they are not in the right part of the plant to affect it," she said.

Kent Police said it had negotiators at the scene. A statement said: "It is thought that 23 Greenpeace protesters are currently on power station property and several of them have chained themselves to generators.

"Police have closed surrounding roads and have already moved on 30 people from the outskirts of the site."

E.ON UK announced in October last year that it planned to build two coal units at Kingsnorth, saying they "state-of-the-art technology" would reduce carbon dioxide emissions.