U.N. Secretary-General Ban Ki-moon says he is urging China and any country with violent protests to use extreme care.

Ban says the United Nations maintains that differences of international and domestic opinion must be resolved peacefully through dialogue.

He says his advice to China and any other country is to take necessary measures to protect the life and safety of civilians.

Ban told reporters in Geneva on Monday that governments also must protect freedom of speech, freedom of assembly and freedom of information.

Ban was responding to a question on violent street battles that killed at least 140 people and injured hundreds in the deadliest ethnic unrest to hit China's western Xinjiang region in decades.