North Korea closed its borders on Tuesday to Malaysians who want to leave the country, spurring Malaysia to issue a retaliatory order and drawing hundreds of ordinary people into an increasingly bitter diplomatic battle over the killing of an exiled member of North Korea’s ruling family.

Malaysian Prime Minister Najib Razak denounced North Korea’s order as a violation of international law, calling it “an abhorrent act, effectively holding our citizens hostage”. The police have been ordered to stop North Koreans from leaving Malaysia “until we are assured of the safety and security of all Malaysians in North Korea”, Mr. Najib said in a statement.

Unprecedented move

The sudden diplomatic escalation came more than two weeks aft