MANILA, May 10 (Xinhua) -- The international environmental organization Greenpeace Saturday said it spotted Filipino fishing ships engaged in illegal transfer of tuna at the high seas in the Pacific near Papua New Guinea.

    The Greenpeace Southeast Asia office said in a news statement that its ship, the Esperanza, exposed an illegal tuna purse seiner, Philippine-flagged Queen Evelyn 168, in a pocket of international waters between Papua New Guinea and the Federated States of Micronesia, on Friday.

    The purse seiner was at the site of a transfer of tuna between her sister vessel and a refrigerated mothership, both also registered to the Philippines.

    "It was likely that a transfer of fish at sea involving an illegal vessel was about to occur, but the arrival of Greenpeace prevented it from taking place as the vessels immediately separated and fled," the statement said.

    "Transfers of fish at sea are well known to facilitate pirate fishing around the world. Now we also have proof of this in the Pacific. It is unacceptable that this is still allowed to continue", the statement quoted Greenpeace Australia Pacific campaigner Lagi Toribau on board the Esperanza as saying.

    "The pockets of international waters between Pacific island countries are especially prone to pirate activities and should be closed down to all fishing," he added.

    The Queen Evelyn 168 is not authorized to undertake any fishing activities in the part of the Pacific, said the statement.

    "At-sea transfers result in massive underestimation of the Pacific tuna catch. For years tuna have disappeared unreported on motherships like this. The Western and Central Pacific Fisheries Commission is supposed to protect tuna from overfishing, but it is clearly failing to do so," said the statement.

    It also said that the only hope for Pacific tuna fisheries and fast-dwindling tuna stocks is the closure of the Pacific Commons to all fishing as marine reserves, and a ban on all transfer of fish at sea.