PYONGYANG, April 16 (Xinhua) -- The Democratic People's Republic of Korea (DPRK) on Thursday night denounced Japan's decision to discharge radioactive wastewater into sea as a "threat to human existence," reported the official Korean Central News Agency (KCNA).

The Japanese government's decision, made in disregard of strong international opposition, would be "another disaster upon mankind suffering from malignant epidemic," the KCNA said in a commentary.

"This is an unpardonable criminal decision posing grave threat to health and security of mankind and ecological environment, which comes to be another clear instance showing Japan's shamelessness and gangster-like nature," said the KCNA.

The radioactive wastewater, accumulated at the Fukushima nuclear power plant since a massive earthquake and tsunami triggered a triple core meltdown in 2011, contains such materials as tritium, cesium and strontium far beyond the tolerable limits, it said.

The radioactive wastewater, if discharged into the sea, will destroy the ecological environment of the sea, a common wealth of mankind, and entail serious risks to health and existence of the people in coastal areas, it said.

For the DPRK, which lies across a sea from Japan, the decision "is a matter of seriousness related to the life and security of our people," it said.

"Japan should immediately withdraw its decision on radioactive water discharge, well aware of the anti-Japanese resentment of our enraged people," it added.

Japanese Prime Minister Yoshihide Suga said Tuesday that his government had decided to discharge contaminated radioactive wastewater in Fukushima Prefecture into the sea.

The decision triggered strong opposition from the Japanese public and global environmental groups. It has also raised concerns from neighboring countries about a possible impact on human health and fishery businesses.