China banned Thursday imports of all seafood products from Japan shortly after the country began releasing treated radioactive water from the crippled Fukushima Daiichi nuclear power plant into the Pacific Ocean, while protests were held in Hong Kong and South Korea.

Chinese customs authorities said they are highly concerned about the risk of radiation contamination following the water release and have strengthened restrictions for food imports from Japan to "protect the lives and health of the people."

Food items other than marine products imported from Japan are expected to be subject to the tighter controls. Prior to the import ban announced Thursday, Beijing had introduced blanket radiation testing on seafood from the neighboring country.

The Chinese Foreign Ministry strongly condemned the ocean discharge and lodged a serious protest, calling it "an extremely selfish and irresponsible act." China's Ecology and Environment Ministry pledged to track and evaluate the possible impact of Japan's water release in its sea areas.

A Shanghai resident in his 50s said the import ban "cannot be helped as bilateral relations are not good," while recognizing that he is not so worried about the risk of radiation contamination from food products.

In Hong Kong, several dozen members of the pro-Beijing Federation of Hong Kong Guangxi Community Organizations protested the water discharge in a rally held in front of the Japanese Consulate General.

People protest outside the building housing the Japanese Consulate General in Hong Kong against Japan's release of treated radioactive water from the crippled Fukushima Daiichi nuclear power plant into the sea on Aug. 24, 2023. (Kyodo)

Chan Kok-caiu, who took part in the rally, told Kyodo News he is worried about the impact of the water release on the human body, comparing it to the 1986 Chernobyl nuclear disaster. "Of course, the effects won't appear immediately, but our health will be seriously affected in the long term," he said.

In a separate rally, another pro-Beijing group expressed its staunch support for the Hong Kong government's decision to ban seafood imports from 10 Japanese prefectures including Fukushima and Tokyo beginning Thursday.

"This is both an act of resistance against the Japanese government as well as an act of protection of Hong Kong's food safety and public health," said group leader So Cheung-wing.

In Seoul, 16 university students opposed to the Fukushima water release were seized by the police for bursting into a building housing the Japanese Embassy.

Civic and environmental groups held protests across South Korea the same day, calling for the withdrawal of Japan's decision to release the water into the ocean, according to local media reports.

The Korea Federation for Environmental Movements rebutted Japan's claims the treated water will have minimal impact on the environment, saying the discharge will inevitably have a toxic influence, Yonhap News Agency reported.

South Korean Prime Minister Han Duck Soo urged Japan to disclose information about the water discharge process, which will continue over the next 30 years, "in a transparent and responsible manner."

North Korea lashed out at Japan going ahead with the discharge, with its Foreign Ministry calling the move "an unethical crime," urging Tokyo to "immediately withdraw" its decision, and adding that the "nuclear-polluted water" seriously threatens "the lives, safety and future of mankind," the official Korean Central News Agency said.

In Taiwan, the Diaoyutai Education Association, which asserts Taiwan sovereignty over the Japan-administered Senkaku Islands in the East China Sea, strongly condemned the Fukushima water discharge and urged the island's leader Tsai Ing-wen not to be a "willing accomplice" of Tokyo's policy.

"This shameless act of beggar-thy-neighbor violates the human rights to health, environment and fishermen's right to survival," the association said, while urging Tokyo to immediately stop the discharge.

Malaysia's Health Ministry said it had started inspections of "high risk food products from Japan" in response to the Fukushima water release.

The ministry did not detail what kind of food products were subject to the inspections, set at the third highest of the six levels regarding food safety, but said fish and fish-based products are among the biggest imports from Japan.

"The Health Ministry is aware of the concerns from consumers on this issue," Muhammad Radzi Abu Hassan, the ministry's director general in charge of public health, said in a statement about the start of the inspections.

Meanwhile, the Philippine government said it will continue to look at the discharge from a "science- and fact-based perspective," despite concerns raised by fishermen groups over its possible negative impact on marine resources.

Manila recognizes the International Atomic Energy Agency's technical expertise on this matter, the Foreign Affairs Department said in a statement.

The IAEA said in a safety review report released in July that the discharge of the treated water "would have a negligible radiological impact to people and the environment."

Pacific island states remain divided over the water release, but will now shift their focus to ensuring Japan is held to account over its safety, Henry Puna, secretary general of the 18-member Pacific Islands Forum, told a press conference in Fiji.

"We've done our best to get Japan not to commence the discharge until there is full agreement that it's verifiably safe to do so. But Japan has taken a sovereign decision," Puna said. "The only option that is open to us now is to ensure that Japan is held accountable to the safety of the water."

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