NANTICOKE, Ont. — Several Greenpeace activists who boarded a coal-toting bulk ore carrier on Lake Erie en route to the Nanticoke power plant have now chained themselves to the ship.

Spokeswoman Joslyn Higginson says the five activists who boarded the Algomarine in a bid to delay the delivery of nearly 30,000 tonnes of coal are now bracing for a visit from police.

She says a police boat arrived shortly after activists Dominique Du Sablon, 20, of Toronto, and Charlie Latimer, 25, of Vancouver, chained themselves to the discharge room.

Higginson says that particular area is where the unloading of coal takes place.

She says a third activist, Emily-Elizabeth Storey, 22, of Toronto, chained herself to the rear of the vessel, making movement of the ship more difficult.

The peaceful protest is aimed at drawing attention to the facility, which is one of several coal-fired plants that Greenpeace says are Ontario's largest contributors to global warming.

The activists arrived at the vessel early today aboard an inflatable craft launched from the Greenpeace vessel Arctic Sunrise, a former icebreaker.

After the group boarded, Higginson said the captain radioed the Coast Guard to have the activists removed, then veered away from the port to await the arrival of authorities.

Higginson said prior to boarding, Greenpeace members painted a slogan on the vessel's hull: "No coal, no nuclear -- clean energy.''

The Nanticoke station is one of four coal-fired electricity plants in Ontario that the Liberal government had promised to shut down by this year -- a deadline that was later extended to 2014.

Green party Leader Frank de Jong applauded Greenpeace's actions, saying the Liberal and NDP plan to phase out coal by 2014 isn't good enough.

While the New Democrats have vowed to close Nanticoke by 2011, the Greens have promised to phase out coal entirely by 2009.

"The end of King Coal is 2009, and Greenpeace is absolutely right,'' de Jong said. "The trouble is you can't vote for Greenpeace, but you can vote for the Green party.''

The Progressive Conservatives have said they will make coal plants cleaner rather than shut them down, and have vowed to cut greenhouse gas emissions to 10 per cent below 1990 levels by 2020.