Japan's deputy prime minister said on Thursday that tensions over an island dispute with China have been fanned by activists, but have not hurt official relations between the countries, AP reported. Deputy Prime Minister Katsuya Okada said the two governments are reacting "calmly" to rising emotions over their longstanding dispute over the uninhabited islands in the East China Sea that Japan calls the Senkaku and China calls the Diaoyu. Tensions have grown since April, when Tokyo's nationalist governor announced he was planning to buy three of the islands from a private family Japan recognizes as their owner. Japan's government is now also talking about buying them. Last month, a group of activists from Hong Kong were arrested and quickly deported after landing on one of the islands, which are controlled by Japan.