The government of the Hong Kong Special Administrative Region (HKSAR) on Saturday reminded local residents now in Vietnam to monitor the situation, exercise caution and attend to personal safety.

The Immigration Department (ImmD) said it had received eight requests for assistance as of 5 p.m. Saturday and has contacted the commissioner of China's Foreign Ministry in the HKSAR, the Chinese Embassy in Vietnam and Consulate General in Ho Chi Minh City for advice and assistance.

All Hong Kong residents who requested for assistance are safe, most of them have returned or will shortly return while the others would remain in Vietnam, the ImmD said.

Currently, international airports in Vietnam and flights between Hong Kong and Vietnam maintain normal operation, said a government spokesman.

Violent anti-China protests and deadly attacks on Chinese companies in Vietnam started on Tuesday after Vietnamese ships and personnel repeatedly harassed the normal drilling operations by a Chinese oil company in undisputed waters off China's Xisha Islands in the South China Sea.

China has lodged a solemn protest with Vietnam and voiced strong condemnation over the violence against foreign companies that has left two Chinese citizens dead and more than 100 others injured.

Chinese Foreign Minister Wang Yi said Vietnam bears unshirkable responsibility for the violent attacks against Chinese companies and nationals. He demanded Vietnam immediately take resolute and effective measures to stop all violence and ensure the safety of the lives and property of all Chinese nationals and companies there.

Vietnamese Prime Minister Nguyen Tan Dung has ordered the concerned authorities to take firm measures to prevent illegal activities, punish perpetrators, and ensure absolute safety of lives and assets as well as the normal operation of all companies, especially foreign invested firms.

He also called on the Vietnamese people not to join "illegal demonstrations" that some say may take place in some cities of the country on Sunday.

In Hong Kong, the Security Bureau issued a Red Outbound Travel Alert for Vietnam on May 15, suggesting local residents intending to visit Vietnam to adjust their travel plans.