Airport frontline authorities at the Kuala Lumpur International Airport (KLIA) and Kuala Lumpur International Airport 2 (klia2) are all geared up to execute the order barring North Korean citizens from leaving the country.

Business was as usual at the two busiest airports in Malaysia even though the authorities including Immigration and police were on a heightened state of alert at their respective bases and stations.

An auxiliary policeman at the KLIA departure hall was seen checking thoroughly passengers' documents and flight details before allowing them to proceed to the Immigration counters.

"We follow orders," he said when asked on the order to bar North Koreans from leaving the country.

Media agencies reported that North Korea barred Malaysians from leaving the country, trigerring a tit-for-tat action by Malaysia.

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Diplomatic ties between Malaysia and North Korea became strained following the murder of Kim Chol, widely reported to be Kim Jong-nam, the half-brother of North Korean leader Kim Jong-un, at klia2 on Feb 13.

It was reported that Jong-nam, who travelled with a passport bearing the name of Kim Chol, was waiting for his flight to Macau at klia2 on Feb 13 when two women suddenly wiped his face with a liquid which was later identified as the VX nerve agent. -- Bernama