This article is more than 6 years old

This article is more than 6 years old

Vietnam has clamped down on anti-China protests after deadly riots triggered by a territorial dispute spooked foreign investors and the country's authoritarian leadership.

Thousands of police and security officers flooded southern Ho Chi Minh City and the capital, Hanoi. Police were posted outside well-known dissidents' houses, preventing them from leaving, according to activists.

In Ho Chi Minh City, police detained several demonstrators after dragging them from a park close to the cathedral. In Hanoi, officials closed off streets and a park close to the Chinese embassy.

As patrol ships from both countries remained locked in a standoff close to a Chinese oil rig in a disputed patch of the South China Sea, Beijing said it had evacuated 3,000 nationals from Vietnam and was sending the first of five ships to retrieve others wanting to leave.

China said it would suspend some of its bilateral exchange plans with Vietnam and was advising its citizens not to travel there.

China's decision to deploy the oil rig on 1 May has been widely seen as it one of its most provocative steps in a campaign to assert its sovereignty in the waters.

Last weekend, Vietnam permitted anti-China protests that drew thousands of people, a rare step that allowed it to amplify state anger against Beijing. Dissident groups joined the protests, and by Tuesday and Wednesday the rallies had escalated into riots targeting factories believed to be owned by Chinese companies, though many of those hit were Taiwanese.

Two Chinese nationals were killed and more than 100 wounded, and more than 1,000 people have been arrested in connection with the violence, which authorities blamed on "extremists".

China has demanded that Hanoi protect Chinese people inside Vietnam, which is heavily dependent on Beijing economically. Hundreds of Chinese have left by commercial flights and across the land border into Cambodia, although there has been calm since Thursday.