North Korea barred Malaysians from leaving the country on Tuesday and Malaysia responded with a similar ban on North Koreans.
"All Malaysian citizens in the DPRK will be temporarily prohibited from leaving the country until the incident that happened in Malaysia is properly solved," North Korea's state-run Korea Central News Agency said, quoting a foreign ministry official.
Malaysia reacted swiftly, condemning Pyongyang's action and barring all North Koreans from leaving the country.
"This abhorrent act, effectively holding our citizens hostage, is in total disregard of all international law and diplomatic norms," Malaysian Prime Minister Najib Razak said.
The moves came as tension continues to escalate over the assassination on February 13 in Kuala Lumpur of a man thought to be Kim Jong-nam, the estranged half brother of DPRK leader Kim Jong-un. Two women are accused of murdering Kim at Kuala Lumpur International Airport, using VX, a nerve agent the UN lists as a banned weapon of mass destruction. South Korea accuses Pyongyang of ordering the hit on Kim.
Speaking to TRT World from Kuala Lumpur, Zan Azlee said eleven Malaysians are thought to be in the DPRK, including two UN workers, and three embassy staff and their families.
Malaysia's prime minister called on North Korea to immediately release all its citizens.
Razak summoned an emergency meeting of the National Security Council and said the ban on DPRK nationals leaving Malaysia would not be lifted until Malaysia is assured that its citizens in North Korea are safe.
Hundreds of North Koreans live in Malaysia. Most of them are workers or students.
In the wake of Kim's murder and criticism from North Korea of its handling of the investigation, Malaysia has already stopped visa-free entry for North Koreans travelling to the country and expelled North Korea's ambassador for questioning the impartiality of the murder probe.
Staff inside the North Korean embassy have also been barred from leaving the premises until their identities have been verified.
Kim Jong-nam murder probe
Malaysian police have identified eight suspects connected to the murder. They believe three of the suspects, including a senior diplomat and a state airline employee, are hiding in the North Korean embassy in Kuala Lumpur.
Police Chief Khalid Abu Bakar has, however, ruled out raiding the embassy, saying it is "only a matter of time" before the suspected killers of the man thought to be Kim come out.
Two women from Vietnam and Indonesia, have been charged over the killing to date. One DPRK national was detained but later released and deported to North Korea due to insufficient evidence.
Four North Korean suspects fled Malaysia shortly after the murder, police say.
The DPRK acknowledges that the dead man is a North Korean national, but maintains that he is not Kim Jong-nam, and that he probably died of a heart attack, not VX poisoning.