Clutching little more than sacks and some with children in tow, more than 140,000 Cambodian migrant workers have fled Thailand since last week out of fear of a crackdown by the ruling junta.
The sudden exodus has flooded the Cambodian border town of Poipet and raised fears of a crisis should more of these low-wage workers get stranded there.
The International Organisation for Migration, which is working with the Cambodian government to transport them home, estimates that up to 18,000 workers crossed the border yesterday.
Its spokesman Joe Lowry said: "For the next few days, there's a need for the transport pipeline to continue. If not, there would be a serious humanitarian issue at the border."
Thailand's junta denied it was cracking down on migrant workers even though they were seen being transported to the Thai-Cambodian border in army trucks.
Thai foreign ministry spokesman Sek Wanamathee told The Straits Times: "It's not forced repatriation or deportation. Because of the large number of foreign workers who wanted to go back voluntarily, the army had to facilitate their transportation to the border with the army trucks."
The Thai labour ministry suggested yesterday that the Cambodians heading home were part of a group of about 40,000 legal migrant workers whose documents had expired and needed to be renewed before they were allowed back to work.
ASEAN's second largest economy currently hosts 2.2 million documented migrant workers - mostly from Myanmar and Cambodia - though the actual number could be as high as 4 million if illegal ones are counted.
These workers power the seafood, construction and other key industries, taking on menial jobs that Thais shun.
Since seizing power on May 22, the junta has suppressed dissent and raided illegal arms caches nationwide.
It has also made clear that it sees illegal workers as a threat to national security.
The National Council for Peace and Order - as the Thai junta calls itself - said in a statement issued on Friday that it intended to "clean up society from illegal activities which include gambling, drugs and illegal workers".
Intriguingly, the fears of a crackdown have not sparked an exodus of Myanmar workers, although the Migrant Worker Rights Network, led by Myanmar nationals, says about 1,000 illegal Myanmar workers have been rounded up and deported by the junta since the coup.
Cambodian Prime Minister Hun Sen is known to have good relations with ousted Thai premier Thaksin Shinawatra.
Pro-Thaksin "red shirt" leaders have sought refuge in Phnom Penh in the past decade of political turbulence.
The junta, which has systematically stamped out red shirt resistance to the coup in northern and north-eastern Thailand, has warned Phnom Penh against allowing it to be used as a staging post to oppose the Thai junta. This is something Cambodia denies.
The Thai foreign ministry's Mr Sek denied there was a political dimension to the exodus.
"We calmed the situation down quite early, so we were lucky that other foreign nationals have not panicked," he said.
This article was first published on June 17, 2014.
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