Australia's government on Thursday released graphic pictures of Japanese hunters harpooning whales and dragging their bleeding carcasses onto a ship near Antarctica, calling it evidence of the "indiscriminate" slaughter of the animals.
Japan denied one of the photographs showed a mother and its calf being killed, and accused Australian officials and media of spreading propaganda that could damage ties between the two nations.
The images were the latest salvo in the new Australian government's stepped-up campaign against Japan's annual whale hunt, which resumed recently after being interrupted by environmental activists who chased the fleet through icy waters at the far south of the world.
The pictures were taken from the Oceanic Viking, an Australian customs service ship sent to monitor the hunt and collect evidence for a legal challenge the government wants to bring against Japan's claim that it kills whales only for scientific purposes.
"It is explicitly clear from these images that this is the indiscriminate killing of whales, where you have a whale and its calf killed in this way," Australian Environment Minister Peter Garrett told reporters.
"To claim that this is in any way scientific is to continue the charade that has surrounded this issue from day one," he said.
The images include video footage of a harpoon being fired into a swimming whale, which writhes as it is hauled toward the ship. The whale eventually stops moving and lies still in bloodstained waters, the harpoon clearly visible piercing its body.
One picture shows two whales - one far smaller than the other - being dragged by ropes or cables up a ramp in the stern of a ship as blood dribbles down.
Hideki Moronuki, chief of the Japanese Fishing Agency's whaling section, denied the photograph depicted a baby whale.
"The fleet is engaged in random sampling, which means they are taking both large and small whales. This is not a parent and calf," Moronuki said in Tokyo.
He also accused Australian officials of getting dangerously close to Japan's whaling ships to take the pictures.
Japan has staunchly defended its annual killing of more than 1,000 whales, conducted under a clause in International Whaling Commission rules that allows whales to be hunted for scientific purposes.
Critics call the Japanese program a disguise for commercial whaling, which has been banned by the commission since 1986.