Demonstrators took to the streets in several Chinese cities on Sunday to protest Japanese activists who landed on the disputed Senkaku islands, known in China as the Diaoyu islands, in the East China Sea, Reuters reported. Onlookers at a demonstration in Shenzhen reported protesters damaging a Honda police car, overturning other cars and waving a Chinese flag. Last week, the Japanese navy arrested 14 Chinese activists after some successfully landed on the disputed islands with flags. In response to the incident, 10 Japanese activists swam to the islands from a boat and hoisted a Japanese flag over the islands. “The illegal behavior of Japanese right-wingers has violated China’s territorial sovereignty,” said China’s foreign ministry in a statement on the incident. Such tit-for-tat maneuvering over the islands has escalated in recent months, not only in northeast Asia but also with China’s neighbors in the South China Sea.