Cambodian PM writes to UNESCO, accuses Thailand of aggression

PHNOM PENH, July 22 (Xinhua) -- Cambodian Prime Minister Hun Sen has written a letter to UNESCO, accusing Thailand of aggression by moving troops into disputed border territory, and warned that Thailand threatened peace in the region. "Thai behavior gravely threatens peace and stability in the region" and Thailand is "defying all principles of international law," Hun Sen said in the letter