The protesters, many of them Vietnamese now resident in Hong Kong, and other supporters, marched peacefully from the government's headquarters in Admiralty to a branch office of China's foreign ministry brandishing red-starred Vietnamese flags, singing patriotic songs and chanting Vietnamese slogans.

The protesters, watched by around two dozen policemen, were led by a young Vietnamese man holding a portrait of their country's late, wispy-bearded revolutionary leader and former president, Ho Chi Minh.

"China, the whole world knows, is now invading into our territorial waters. … We love our country," said one of the protest organisers, Mo Pak-fung.

"We are coming out today because we hope China will leave Vietnam. … We don't want a war to occur," added Mo, who comes from Vietnam but has lived in Hong Kong for the past 25 years.

Tensions flared between Vietnam and China after Beijing deployed an oil exploration rig in disputed waters near the Paracel Islands, which China calls the Xisha Islands and Vietnam calls the Hoang Sa Islands.

Protesters in Hong Kong waved several banners reading, "We love Peace withdraw 981 oil rig out of Vietnam sea", and "We need help from international communities". They did not rule out further action in Hong Kong.

The placement of the oil rig to a location 240km off Vietnam's coast in an area both counties claim unleashed a deadly wave of violence across Vietnam as thousands of protesters rampaged in industrial zones.

Vietnam says the islands fall within its continental shelf and a 200-nautical-mile exclusive economic zone.

Reuters - May 26, 2014