Six opposition political parties jointly slammed Japan’s decision to start releasing wastewater from the crippled Fukushima nuclear power plant into the ocean on Thursday as an international maritime crime.

Lawmakers from the main opposition Democratic Party(DP), the minor Justice Party and four others gathered in front of the Japanese consulate general on the southernmost Jeju Island to criticize Tokyo for causing a worldwide calamity to resolve a domestic problem.

They also directed their ire at the Yoon Suk Yeol administration for endorsing Japan's discharge plan despite opposition from over 80 percent of the South Korean people.

Local civic groups have held single-person relay rallies and press events down south in Busan, Gwangju, South Jeolla Province, and South Gyeongsang Province, demanding a withdrawal of the plan and some calling to take Japan to the International Tribunal for the Law of the Sea.

Such acts of protest are planned for the evening by local groups in Incheon, the Gyeonggi provincial city of Bucheon and Ulsan.