Students protesting against the renewal of the U.S.-Japan security pact clashed with 20,000 riot police in Tokyo on Sunday (June 14) Although a protest march by about 25,000 left-wingers from western Tokyo to the city centre passed off peacefully, extremist groups scattered throughout the city fought police with petrol bombs, stones, bamboo poles and steel pipes. More than 200 demonstrators were arrested.

Demonstrators rallied first in Yoyogi Park, Park, with different speakers condemned the Japanese the Japanese government's decision to renew the U.S.-Japan mutual security agreement.

The 10-year-old security pact will be automatically renewed at midnight next Monday (June 22) as the result of a meeting between Japanese Prime Minister Eisaku Sato and President Nixon at Washington, D.C. last November. Under the agreement the United States commits itself to help defend Japan in return for being allowed to maintain bases there.

Although the agreement can be scrapped by either side on 12 month's notice, both nations have indicated they place to maintain it for some years to come. Left-wing groups are demanding abrogation of the treaty as a first step towards unarmed neutrality because they are afraid that Japan will become involved with the U.S. in an Asian conflict.

As the demonstration progressed through the streets of Tokyo, police were mobilised to guard the Diet (Parliament), the official residence of the Prime Minister, and the U.S. Embassy. Earlier, 88 students were arrested near Yoyogi Park when they were found carrying Molotov cocktails.

Twenty-thousand riot police are being mobilised again on Monday (June 15) when memorial rallies are being planned at two universities to commemorate the death of a young girl student who was trampled to death during fighting at the Diet building in the anti-treaty riots of 1960.