Japan's industry minister has paid a visit to Fukushima Prefecture. He sampled some of the local seafood, after Japan began discharging treated and diluted water from the damaged Fukushima Daiichi plant last week. It's part of a push to prevent any harmful rumors.

Industry minister Nishimura Yasutoshi tasted sashimi caught off the coast of Fukushima Prefecture on Friday, just one day after the release began.

Nishimura also met with local business owners, telling them the government is committed to transparency.

He said: "We will continue to confirm the safety and disclose all of the data in a transparent manner. That is the best way to prevent any reputational damage."

Japan's Fisheries Agency has analyzed fish caught within 10 kilometers of the plant. It says it found that levels of tritium were below what's considered "detectable."

But that hasn't stopped an apparent harassment campaign.

The Fukushima Daiichi plant's operator says it's received 6,000 spam calls since the release began. They appear to be originating from China. A number of unrelated Japanese businesses, including hotels and restaurants, have also been targeted.

Prime Minister Kishida Fumio has urged Beijing to address the harassment campaign. He says China should be open to a scientific dialogue.

Kishida said: "Without that discussion, numerous spam calls, believed to be from China, have been made. People have thrown stones at the Japanese embassy and Japanese schools in China. This is obviously regrettable."

NHK spoke with an expert who says China may be allowing the campaign to continue to deflect attention away from domestic issues.

Professor Korogi Ichiro of Kanda University of International Studies said: "China's economy is very sluggish and serious problems have emerged, such as the property sector crisis and a high youth unemployment rate. The government may be using the release to help vent some of the discontent building in Chinese society."

Korogi also says China's suspension of all Japanese seafood imports could be used as a diplomatic tool in other trade disputes between Beijing and Tokyo.

The Fukushima Daiichi nuclear power plant suffered a triple meltdown in the 2011 earthquake and tsunami. Water used to cool molten fuel at the plant has been mixing with rain and groundwater, seeping into damaged reactor buildings.

The water is treated to remove most radioactive substances, but still contains tritium. Before releasing the treated water into the sea, the plant's operator dilutes it to reduce tritium levels to about one-seventh of the World Health Organization's guidelines for drinking water.

Before the accident, Fukushima Daiichi discharged around 2.2 trillion becquerels of tritium into the ocean per year.

Under the current plan, the plant's operator says it will not exceed 22 trillion becquerels annually. That is far lower than tritium released from other nuclear facilities around the world, including in South Korea and China.