Vietnam pledged on Saturday to quell any outbreak of violence after protests against Beijing this week devastated key industrial centers, due to discontent with the Asian giant oil drilling in a disputed area in the South China Sea South.
The principal investigator of the Vietnamese police defended the security forces, accused of failing to control disorder and said "illegal acts" will not tolerate a day before planned protests against China in its major cities.
Hoang Kong Tu said to the media that the authorities would apply the full force of the law and that the violence Tuesday and Wednesday would not be repeated, when groups of protesters attacked industrial parks in three provinces vital for the economy and exports Vietnamese.
Riots erupted Tuesday against China in the south, in response to the installation of an oil rig by Beijing in an area of the South China Sea claimed by Vietnam, the United States said decision was provocative.
On Saturday, the Ministry of Foreign Affairs of China advised its citizens to avoid travel to Vietnam.
The head of public security of China urged Vietnam to take measures to stop violence against China and to punish those who would cause riots.
"We are deeply dissatisfied with the failure of the Vietnamese side to respond effectively to contain an escalation of the situation," said Guo Shengkun in a telephone conversation with his Vietnamese counterpart, was quoted Saturday by the Chinese news agency Xinhua.
(Additional reporting by Chen and Niu Shuping Aizhu in Beijing, written by Martin Petty, In Janisse Huambachano)