Japanese Prime Minister Taro Aso returned home early Sunday from Thailand after massive antigovernment demonstrations forced cancellations of regional summits in Pattaya.

Aso held separate meetings with Chinese Premier Wen Jiabao and South Korean President Lee Myung Bak and also took part in a trilateral meeting with them, before cutting short his stay in the Thai resort city and heading home.

Thai Prime Minister Abhisit Vejjajiva declared a state of emergency in Pattaya while leaders from the Association of Southeast Asian Nations and their dialogue partners outside the 10-member group were evacuated by helicopter from the rooftops of hotels or by Thai navy vessels.

The so-called ASEAN-plus-three summit Saturday and the 16-nation East Asia Summit on Sunday were both canceled.