An armed Japanese escort ship collided Sunday with a Greenpeace boat tracking a freighter laden with highly toxic plutonium, the environmental group and Japan's coast guard said.
Japan is shipping the plutonium home to fire up a new generation of nuclear fast-breeder reactors. Greenpeace opposes the shipment and is trailing the cargo ship, saying the plutonium poses huge dangers ranging from a spill to an attack by terrorists seeking nuclear bomb-making material.
The Akatsuki Maru, carrying 1.7 tons of plutonium, left the French port of Cherbourg late Saturday after a day of clashes between security forces and environmentalists.
The vessel's route on its two-month voyage to Yokohama is secret.
But Greenpeace said the freighter and its armed escort, the Shikishima, were sailing southwest in the Atlantic and could reach Portugal's Azores Islands by Wednesday.
On Sunday, Greenpeace said the Shikishima rammed its ship, the Solo, in the English Channel. It said the Japanese warship's helicopter landing decks were damaged, but reported no injuries.
Greenpeace Capt. Albert Kuiken said the Shikishima was badly dented on the starboard side. He said a side railing also was ripped off; he described damage to the Solo as light.
In Tokyo today, Japan's coast guard, the Maritime Safety Agency, issued a statement saying the Solo, after following at a close distance, ran into the Shikishima's after starboard quarter twice despite warnings and evasive maneuvers by the Japanese ship.
The agency said the collision took place Sunday morning in international waters north of the French peninsula of Brittany.