Over 400,000 nuisance calls in total have been made to the Japanese Embassy in Beijing since the release of treated radioactive water from the crippled Fukushima nuclear power plant into the sea began in late August, Japanese government sources said Tuesday.

On the back of growing anti-Japan sentiment in China, the daily number of harassing calls received by the embassy peaked at more than 40,000 on Aug. 25, a day after the ocean discharge started, and has stayed at around 10,000 recently, they said.

Photo taken on Sept. 18, 2023, shows the Japanese Embassy in Beijing. (Kyodo)

Tokyo has repeatedly asked the Chinese government to deal with the calls, saying they impede operations at the embassy, but the situation has yet to improve, according to the sources.

Similarly, Japan has experienced a surge in nuisance phone calls believed to originate from China, while also witnessing online appeals in China to boycott Japanese products.

In most cases, callers harshly criticized Japan over the Fukushima water release or remained silent. Some threatening calls have also been made to the embassy, the sources said.

The embassy has maintained records of phone numbers associated with severe harassment calls and has reported them to Chinese public security authorities.

"We should never silently endure" the harassment, a Japanese government official said.

Chinese laws stipulate that individuals who frequently make nuisance calls to disrupt other people's lives should be held accountable. A Chinese government official emphasized that China is governed by the rule of law and takes necessary measures to address criminal acts.

Beijing remains strongly opposed to Japan's ocean discharge, calling the water "nuclear-contaminated" and demanding its immediate halt.

Chinese Foreign Ministry spokesman Wang Wenbin said at a press conference on Aug. 30 the root cause of the current situation lies in the fact that Japan "unilaterally and forcibly" started the ocean discharge, sparking "widespread indignation from the international community."

Wang added China protects the safety of foreign diplomatic and consular missions and the lawful rights and interests of foreign citizens in China in accordance with the law.

In response to the water discharge, China imposed a blanket import ban on Japanese fishery products. The International Atomic Energy Agency concluded in a report in July that the Fukushima water release plan aligns with global safety standards and will have a "negligible" impact on people and the environment.

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