Anti-nuclear protesters gather at a rally in Tokyo Sunday, Dec. 22, 2013. Over a thousand protesters surrounded the Diet building demanding an end to atomic power and not to re-open nuclear power plants shut down after the 2011 meltdowns at the Fukushima Dai-ichi nuclear power plant. Placards worn by the protesters read: "No nukes." "Don't resume operations of nuclear power plants." (AP Photo/Shizuo Kambayashi)TAIPEI, Jan. 15 (Kyodo) — A Japanese engineer who helped build part of the Fukushima Daiichi No. 4 reactor said in Taiwan on Wednesday that the safety of nuclear power plants is unpredictable, urging Taiwan to ditch atomic energy for renewable resources.

Mitsuhiko Tanaka, who arrived in Taiwan on Tuesday with a delegation of Japanese parliamentarians for a six-day visit, told a press conference in Taipei that the Chernobyl nuclear meltdown in 1986 changed his views on nuclear power.

"Nuclear accidents are bound to happen someday, only that we don't know when they will happen," he said.

Tanaka, who helped build part of No. 4 reactor of the Fukushima Daiichi plant while working at Hitachi Ltd. in 1974, quit the company in 1977 and became a writer.

He chronicled a manufacturing defect in the steel vessel installed at No. 4 reactor and the subsequent cover-up in a book he published in 1990.

He also went to the Japan's Ministry of International Trade and Industry in 1988 to report the cover-up, but the government refused to investigate and Hitachi denied his accusations.

Little did he know that the manufacturing defect would resurface decades later after a powerful earthquake hit the plant on March 11, 2011, triggering a tsunami that disabled its cooling systems and caused Japan's worst-ever nuclear accident.

Reactor 4 was shut for maintenance during the crisis but was hit by explosions and a fire that spread from adjacent units.

At the press conference, House of Representatives member Taro Kono also voiced his strong opposition to the nuclear industry.

Urging Taiwan's government to make information open to the public, Kono expressed regret over the refusal of Taiwan Power Co., the operator of the island's three nuclear power plants, to let the delegation from Japan visit one of them.

Kono campaigned in 2009 to become president of Japan's Liberal Democratic Party, a position once held by his father Yohei Kono, but he lost the bid. He said his colleagues urged him during the campaign to refrain from opposing nuclear energy.

"I hope Taiwan doesn't repeat the same mistake as we did," he said.

Tanaka and Kono are among the many Japanese who have either turned their back on or ramped up their opposition to the nuclear industry after the Fukushima incident.

Former Japanese Prime Minister Naoto Kan, who visited Taiwan in September last year, called here for the closing of all nuclear power plants and abandoning of nuclear energy.

Two more former Japanese prime ministers, Junichiro Koizumi and Morihiro Hosokawa, have also joined the chorus of challenging incumbent Prime Minister Shinzo Abe's pro-nuclear power policy.

With Koizumi's backing, Hosokawa is seeking to become Tokyo governor on an antinuclear energy platform.