Tokyo  - Members of the environmental group Greenpeace on Tuesday launched a major anti-whaling campaign in Japan, protesting the arrest of two activists who investigated corruption in the country's whaling industry.

Junichi Sato and Toru Suzuki, who were arrested in June for allegedly stealing two boxes of whale meat, face up to 10 years in prison.

Greenpeace, which protested against the "politically motivated" arrests in front of Japan's parliament building, said the two men had only tried to gather evidence in an attempt to expose a corruption scandal in the whaling industry.

Crew members of Japan's whaling fleet have been smuggling whale meat off their ships to sell it on the black market, the environmentalists said.

"It's not Greenpeace activists who should be put on trial, it is the government-backed whaling programme in the Southern Ocean Whale Sanctuary," said Jun Hoshikawa, executive director of Greenpeace Japan.

The group presented a letter to the office of Prime Minister Taro Aso, urging an end of the government-funded whale hunts in the Southern Ocean.

Since a whaling moratorium came into force in 1986, Japan has continued to hunt whales for what it has called "scientific purposes." (dpa)