“I suggest them to follow the official instructions published in Israel and be in touch with their embassy,” Lati told the Post, while calling the Hamas operation “a cowardly attack against civilians”.

He warned of an escalation of violence, arguing it was the duty of every government to protect its citizens against any terrorist attack.

“What we know is that yesterday there was a vicious terrorist attack … [on] the Jewish and Israelis in towns in Israel,” he said. “There are hundreds of casualties. Civilians were slaughtered, civilians were taken as hostages and brought … back to the Gaza Strip. Children, old people, families.

“What we know is that our army will strike back and strike in a very severe way.”

When asked what message he would convey to the hundreds of Israeli nationals in Hong Kong, Lati called on them to remain united and confident in their country’s ability to “recuperate, recover and strike back [at] the terrorists”.

Israel declared a rare state of alert for war on Saturday after Hamas fired an estimated 2,200 missiles out of Gaza into the country’s towns and infiltrated parts of its south.

Hamas, which rules Gaza and is classified as a terrorist organisation by the United States, has said its attacks were the start of a major operation.

The Chinese foreign ministry urged relevant parties “to remain calm, exercise restraint and immediately end the hostilities to protect civilians and avoid further deterioration of the situation”.

“The fundamental way out of the conflict lies in implementing the two-state solution and establishing an independent State of Palestine,” the foreign ministry said.

The Immigration Department told the Post that all feasible assistance has been offered to Hong Kong residents in Israel and its officials would monitor the situation.

The department also reminded Hong Kong residents who remained in the area that they could call its 24-hour hotline at (852) 1868 for assistance.

They can also use the “ImmD Mobile App”, send a message to the 1868 WhatsApp hotline or submit an online form for assistance as well.

They can also reach out to the consular protection and assistance hotlines of the Chinese embassy in Israel at (972) 3-5459 520 or the Chinese Office in Palestine at (970) 595 776 516 for assistance.

The Security Bureau upgraded the travel alert from yellow to red on Sunday.

A government spokesman said: “Residents who intend to visit Israel should adjust their travel plans and avoid non-essential travel, including leisure travel. Those already there should monitor the situation, exercise caution, attend to personal safety and avoid protests and large gatherings of people.

Residents should avoid all travels to Gaza and nearby areas as well as areas along the border with Syria and Lebanon due to the volatile security situation.”

The red alert is the second level of a three-tier system and warns of a “significant threat” at the destination involved.

According to the Trade and Development Council, Israel was Hong Kong’s 26th largest trading partner, accounting for 0.28 per cent of total trade, last year.

Catherine Leung, the co-founder and partner of MizMaa Ventures, a venture capital firm that invests in Israeli entrepreneurs, and chairwoman of the Chamber of Hong Kong Listed Companies, said she remained confident in the investment prospect in the country.

“While wars are unfortunate, Israel always manages to do better from these wars, and venture capital continues to back the best companies in the country, many of which were founded based on the sensor, data analytics and cybersecurity technologies needed for [the nation’s] defence,” Leung said in her personal capacity as an investor in Israel and the Middle East.

“I don’t see that changing any time soon.”