By Keiji Hirano and Janice Tang YAIZU, Japan, March 1 Kyodo - Nuclear bomb sufferers and their supporters reiterated their call for the elimination of nuclear weapons on Monday, the 50th anniversary of the 1954 U.S. hydrogen bomb test at Bikini Atoll in the central Pacific.

The bomb test exposed the Japanese fishing boat Fukuryu Maru No. 5, known in English as the Lucky Dragon, and residents of Rongelap Island to radiation.

On Monday, about 2,000 people marched 2 kilometers in chilly weather in Yaizu, Shizuoka Prefecture, the home port of the trawler, to the grave of crewman Aikichi Kuboyama. They paid tribute by laying red roses, his favorite flower, on the grave and offering incense.

Kuboyama, the ship's chief radio operator, died six months after the blast at age 40, becoming a symbol of the radiation disaster. His dying wish was that he be the last victim of a nuclear bomb.

The mayors of Hiroshima and Nagasaki, the only cities ever hit by nuclear bombs, both sent messages calling for more efforts to abolish nuclear weapons and to ensure that the destruction caused by nuclear bombs is not forgotten. The United States dropped atomic bombs on the cities in August 1945.

Hiroshima Mayor Tadatoshi Akiba called for more efforts to teach young people and the world about the experience of the two cities. Nagasaki Mayor Itcho Ito said the global nonproliferation framework is threatened by countries that continue to hold on to their nuclear arms and others suspected of having obtained such weapons.

At an assembly in Yaizu, former crew member Yoshio Misaki, 78, said, ''The tragedy of 50 years ago must not be repeated in the 21st century.''

John Anjain, who was the community leader of Rongelap Island when the U.S. tested the hydrogen bomb ''Bravo'' at Bikini Atoll on March 1, 1954, visited Yaizu for the anniversary.

''On the day of the hydrogen bomb blast, white powder fell on us like snow,'' Anjain, 81, said at the assembly. ''We soon began to feel sick and our hair started falling out.''

''We have experienced all sorts of hardships since 1954, but it is my honor to be here in Yaizu on the 50th anniversary,'' he told the audience of 1,300.

The assembly participants adopted a statement urging the elimination of nuclear weapons ahead of the 60th anniversary in 2005 of the atomic bombings of Hiroshima and Nagasaki.

At another assembly in the city of Shizuoka in the evening, Hiromitsu Toyosaki, a freelance photographer who has covered the victims of nuclear tests around the world during the past decades, said, ''We experienced 'Chernobyl in the ocean' 50 years ago.''

''People at Bikini Atoll have been left behind in the central Pacific with fears that the harmful influence of radioactivity may be passed on to their future generations,'' he said, stressing the need for Japan to consider how to support them.

Of the 23 members of the crew of the 140-ton Lucky Dragon, 12 including Kuboyama have died, most after years of treatment for illness believed to be linked to their radiation exposure. Most surviving members have also suffered serious health problems.

The crew members were fishing for tuna about 160 km east of the test site at the time of the hydrogen bomb explosion. The bomb was 1,000 times more powerful than the atomic bomb dropped on Hiroshima.

Despite the hardships the survivors have endured, they have been excluded from the Japanese government's relief measures for atomic-bomb survivors in Hiroshima and Nagasaki, and have never been recognized as victims of a nuclear bomb.

Participating in the event for the first time, Joseph Gainza from the American Friends Service Committee (Quakers) in Vermont said, ''I think it was a very unfortunate but a very political decision made by the Japanese government under pressure from the United States not to publicize the incident.''

''The U.S. government wants to keep from American people the truth of nuclear weapons,'' Gainza, 60, told Kyodo News. ''They want to keep the myth that nuclear weapons are a way to protect U.S. freedom…If people in the U.S. understood it better, maybe we can get the U.S. government to sign a (nuclear arms) abolition treaty.''

Yoko Honjo, 60, who traveled to Yaizu from Tokyo, said it was the eighth time she has taken part in the event.

''I was too young at the time of the incident to remember much, but I visited the Daigo Fukuryu Maru Exhibition Hall in Tokyo and was touched by Mr. Kuboyama's dying wish that he be the last nuclear victim,'' she said after visiting the grave.

A series of anniversary events, including symposiums and assemblies, were held over the weekend in Yaizu and Shizuoka as well as in Tokyo to raise awareness and remind people of the tragedy. ==Kyodo Fishermen exposed to H-bomb test want nuke victim status By Keiji Hirano YAIZU, Japan, March 1 Kyodo - A former crew member from the fishing boat Fukuryu Maru No. 5, which was exposed to radiation when the United States tested a hydrogen bomb on the Bikini Atoll 50 years ago to the day, urged the government to recognize the crew members as nuclear-bomb victims.

Matashichi Oishi, 70, laid flowers at the graves of three crew members of the vessel, better known overseas as the Lucky Dragon, in the port city of Yaizu in Shizuoka Prefecture.

''They suffered a lot as H-bomb victims and died after repeatedly being hospitalized,'' he said. ''I strongly hope the government will recognize they died from the radiation, not from ordinary diseases.''

The three, who died in their 40s and early 50s of liver diseases, are among the 23 crew members of the Fukuryu Maru, which was showered with radioactive ash.

The U.S. dropped the hydrogen bomb, code-named ''Bravo,'' on the atoll, which is part of the Marshall Islands, on March 1, 1954. It was 1,000 times more powerful than the atomic bomb the U.S. dropped on Hiroshima in 1945.

Of the 23, 12 have died, most after years of treatment for illness believed to be caused by their exposure to radiation.

Most surviving members, including Oishi, have suffered serious health problems following the Bikini exposusre.

Oishi referred to the Japanese government's stance of not recognizing the crew members as nuclear-bomb victims -- known as ''hibakusa'' in Japan -- unlike atomic-bomb survivors in Hiroshima and Nagasaki, and therefore excluding them from relief measures.

Japan adopted that policy after the U.S. agreed to pay each crew member an average of 2 million yen as ''sympathy money'' in a political settlement.

''The government should have conducted follow-up investigations over our health conditions, but we have been left behind without official support because of the political settlement. If the dead members were still alive, they would get angry,'' Oishi said in front of the graves.

He said the government should compensate the bereaved families of dead victims and pay for the medical treatment of those who are still alive.

''I have lived longer than my fellow crew members, and I believe it is my duty to speak up to the public, instead of them, about our bitter experiences so that memories of the Bikini incident will not fade away,'' he said.

On the Marshall Islands, 840 people are believed to have died of health problems caused by the nuclear tests in the Pacific from 1946 to 1958. Another 1,000 islanders still suffer from conditions such as leukemia and other types of cancer. ==Kyodo