More than 40 Singaporeans still remain in conflict-ridden Yemen, according to estimates from the Ministry of Foreign Affairs (MFA).
The Straits Times understands that most of the group - made up of students, housewives and businessmen - have chosen to stay, despite repeated attempts by the ministry to get them to leave the country for their safety.
Minister for Law and Foreign Affairs K. Shanmugam yesterday appealed to their sense of personal responsibility to leave immediately and not put themselves at serious risk.
"The more they continue to be there, the more they are putting themselves at risk, and it becomes more and more difficult for any sort of rescue operations to be conducted," he said.
A total of 25 Singaporeans have left Yemen with the MFA's assistance over the past two weeks.
Over the weekend, eight Singaporeans from Tarim in south Yemen were evacuated to Oman by coach.
Most of them are students and they arrived back in Singapore on Tuesday.
The MFA worked with Malaysia to assist another woman to leave Tarim on Tuesday and she is on her way home.
China, the Philippines, India, Indonesia and Oman have also helped Singapore in its rescue efforts.
A Crisis Response Team has been deployed in Oman and the MFA is planning another wave of evacuations later this week.
The ministry has issued three travel advisories on Yemen since September last year, when Houthi rebels took control of Yemen's capital Sanaa.
Evacuation efforts intensified last month when Saudi Arabia began air strikes against the Houthis.
It is not known how many Singaporeans are residing in Yemen, but religious scholars say there are about 60 students studying in religious schools such as Rubat Tarim and Darul Mustafa in Tarim at any one time.
These schools are famed for their religious instruction because they preach the same "tolerant and open-minded" brand of Islam that is familiar to Singaporeans, said Dr Susanne Dahlgren, visiting research associate professor of the Middle East Institute at the National University of Singapore.
Others say students flock there because they are attached to religious teachers who are allegedly descendants of the Prophet.
"Most of the Singaporeans there are either students or those who chose to live there with their relatives," said Mr Ameen Talib, 52, a prominent member of the Arab community here.
He has a brother who was a minister in the Yemeni government.
Another brother, Mr Helmi Talib, is Singapore's Non-Resident Ambassador to Yemen.
There are some 20,000 to 30,000 Arabs in Singapore and almost all have ancestral links to Hadramawt in southern Yemen.
Singapore's strong social and business ties with Yemen go all the way back to the 19th century, when they traded spices and incense.
Business ties have waned over the years, leaving only the odd trader who gets shark's fin and sea cucumber from Yemen to sell to Chinese wholesalers here.
But many continue to stay connected with their relatives in Yemen.
"We follow the news closely here on Al Jazeera or other Arabic news channels on a daily basis because we have family there," said Mr Talib, a business consultant.
Yesterday, Mr Shanmugam said Singapore should draw some lessons from its previous evacuation experiences with Syria.
He said: "Despite many advisories, some of our people did not leave Syria in time and then they found that all their escape routes were cut off, and leaving Syria became extremely difficult."
Similarly, he said that many embassies in Yemen have closed down and are winding down rescue operations.
"So really, those who are there should leave immediately."
MFA ACTION SINCE SEPTEMBER
From as early as September, the Ministry of Foreign Affairs (MFA) has taken various steps to evacuate Singaporeans from Yemen. Here are some of the key events:
Sept 16: MFA issues the first advisory for Singaporeans to leave Yemen
Sept 21: Houthi rebels take control of Yemen's capital, Sanaa
Nov 25: MFA issues the second advisory and started contacting Singaporeans to leave the country
Jan 19: Houthi rebels attack the presidential palace in Aden
March 26: Saudi Arabia begins air strikes against rebels
March 27: Third advisory is issued
March 31: MFA works with China to help a family with four children leave Aden on a Chinese vessel
April 3: Then Senior Minister of State for Foreign Affairs Masagos Zulkifli seeks Oman's assistance during his visit there
April 11: Crisis Response Team is despatched to Oman to coordinate evacuation efforts
This article was first published on April 16, 2015.
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