A pod of killer whales trapped by drift ice off the coast of Hokkaido, Japan’s northernmost main island, have apparently safely escaped, officials have said. The orcas were initially spotted by a fisher who reported them to officials in the town of Rausu, on the north-east coast of Hokkaido, on Tuesday morning. After environmental groups raised concerns, town officials travelled to the coast later on Tuesday and saw about a dozen orcas bobbing up and down in a tiny gap surrounded by drift ice about half a mile offshore. They returned to the coast on Tuesday evening and saw that the pod had moved to the north, and it was gone when they returned again on Wednesday, said Masataka Shirayanagi, a Rausu official. Officials said they believed the orcas were able to free themselves as gaps between the drift ice grew. Shirayanagi said: “We believe they were able to escape safely.” Footage captured by a drone flown by a conservationist group and shown on NHK national television and social media had prompted concern in and outside Japan about the condition of the orcas and pleas for the Japanese government to help. One group submitted a request to the defence ministry to mobilise an ice breaker to help free them. Although the trapped whales were in Japanese waters, they were not far from an island that is disputed by Japan and Russia. Japan marked the annual Northern Territory Day on Wednesday to renew its demand for the return of the Russian-held islands. The dispute over the islands, which the former Soviet Union seized from Japan at the end of the second world war, has prevented the two countries from signing a peace treaty formally ending hostilities. Moscow announced it was cutting off negotiations with Tokyo over Japanese sanctions after Russia’s invasion of Ukraine. The chief cabinet secretary, Yoshimasa Hayashi, told reporters on Wednesday that orcas were not a designated endangered species and officials were monitoring the situation.