In Ho Chi Minh City on Sunday morning, a heavy police presence armed with batons and wearing helmets, cordoned off the demonstrators as their numbers rose and they started to march towards the Chinese consulate general just ten minutes away.

Police stopped them after they were less than halfway into their journey, and brief clashes erupted between demonstrators and what appeared to be security personnel in plainclothes. A local said some protesters had attempted to display banners critical of the Vietnamese government.

Some demonstrators were then taken away.

As in previous days, the government had sent text messages on Sunday morning to mobile phones throughout the country calling on residents not to participate in illegal protests.

Protest organisers’ pamphlets reviewed by the Post indicated that demonstrations would continue until Sunday afternoon. A heavy police presence throughout Ho Chi Minh City and vans with loudspeakers calling for calm on Sunday morning attested to authorities expecting more unrest.

Meanwhile, a peaceful protest was reported in downtown Hanoi. Residents in the areas most affected by intense looting earlier this week, Binh Duong and Ha Thinh provinces, said they had not seen crowds gathering there.

Witnesses and journalists wrote on social media networks that police had dispersed a gathering outside the Chinese embassy in Hanoi, calling it illegal. Authorities closed off streets and a park close to the embassy, and police were posted outside well-known dissidents houses, preventing them from leaving, according to activists.

The witnesses added police and plainclothes men with earpieces had prevented reporters from talking to demonstrators in Ho Chi Minh City.

Police and military police units have been deployed at the gates of industrial parks in and around Ho Chi Minh City since Saturday evening, according to a Taiwanese businessman who said he had been coordinating emergency efforts within the community. “The situation is very quiet now,” he said.

The demonstrators on Sunday comprised of urban intelligentsia, professionals and retired government officials, said Carlyle Thayer, a Vietnam scholar at the University of New South Wales and the Australian Defence Force Academy.

“This group contains a sub-stratum of protesters who want to expand the agenda beyond opposing China to criticism of the government on a range of issues such as corruption and the arrest of bloggers and electronic journalists,” he said.

China, meanwhile, said it had dispatched the first of five ships to Vietnam to speed up the evacuation of any its citizens wanting to leave.

More than 3,000 Chinese have already been pulled out from Vietnam following the riots this past week that left two Chinese dead and injured about 100 others, the Foreign Ministry said in a statement.

China deployed an oil rig to a disputed patch of the South China Sea on May 1, triggering fury in Vietnam. Hanoi sent ships to confront the rig in a tense standoff with Chinese vessels. The breakdown in ties between the two countries is the most serious since 1979, when they fought a brief but bloody border war.

Last weekend, Vietnam allowed anti-China protests that drew thousands of people, a rare step widely seen as a way of amplifying state anger against Beijing. Doing so was risky for authorities: dissident groups joined in the protests, and public anger was such that violence was a possibility.

By Tuesday and Wednesday, the protests had morphed into riots targeting factories believed to be owned by Chinese companies. Many of those hit were Taiwanese. The violence caused concern among foreign investors who have turned Vietnam into a manufacturing hub in recent years.

China has loudly demanded Vietnam protect Chinese people inside the country. Many Chinese have left by commercial flights and across the land border into Cambodia, although violence has stopped since Wednesday.

Vietnam’s government has vowed to protect all foreign investors, including Chinese, and said it has arrested more than 1,000 people over the rioting. On Saturday, it said further protests would not be allowed.

“I want to send a message that if we don’t stop China today, tomorrow it will be too late,” said demonstrator Dao Minh Chu, as he was pushed away from the park near China’s embassy, where last week around 500 people gathered without interference from authorities. Those protests were covered enthusiastically by state media, a clear sign of state sanction.

China is a vital economic trade partner for Vietnam, and business links have grown in recent years. While they share a political ideology and a commitment to authoritarianism, the two countries also have a long history of bad blood. Many Vietnamese harbour deep resentment over what they see as China’s bullying and economic exploitation of Beijing’s far smaller neighbour.

They have often sparred over overlapping claims in the South China Sea, which is believed to have significant oil and gas deposits.

China has been much more assertive in pressing its territorial claims in recent years, often bringing into it into dispute with Vietnam and the Philippines. Spats have broken out over fishing rights and oil exploration missions in recent years, but the placement of the rig 220 kilometres off the coast of Vietnam was considered especially provocative.

Vietnam’s government doesn’t allow basic political freedoms and routinely arrested free speech activists and others challenging one-party rule. Anti-China protests are one of the few opportunities for public gatherings in Vietnam and also attract dissident groups, who often claim Hanoi is too soft on Beijing.

Several well-known activists said they had been prevented from leaving their homes to attend the rally.

“I think the best way is to allow people to protest,” said La Viet Dung, a frequent anti-China protester, adding that police visited him late on Saturday asking him not to attend. “They say they are preventing people from protesting because they are worried about extremist actions and violence, but that is not logical.”

09.49 A larger than usual police presence, consisting of small groups of policemen wearing helmets and holding batons, stand at most intersections next to red and white mobile fences.

10.45 March starts, with whistles and clapping.

10.49 Protesters shouting “Vietnam”. More than one hundred demonstrators walking from youth culture centre towards consulate.

10.52 Groups joining protest at Notre Dame cathedral. Police regulate traffic, allowing the protest.

10.55 Slogan on banners: “Make oil rig go away / Use the military to retake islands / Paracels and Spratleys are Vietnamese”.

10.57 Small group of demonstrators briefly clash with police at Notre Dame cathedral. Police sirens are heard as area is closed off.

11.00 More security arriving on bus.

11:05 Demonstration route closed off.

11:09 Loudspeakers from vans call on demonstrators not to commit crimes.

11:45 No demonstrators outside the Chinese consulate, protest near the Notre Dame Cathedral dispersed.