BANGKOK (AFP) - Thai authorities said on Tuesday arrest warrants have been issued for three more military officers over human trafficking, as part of a crackdown that sparked a regional migrant crisis earlier this year.
Previously only one senior officer - Lieutenant-General Manas Kongpan - had been charged over the smuggling of Rohingya Muslim and Bangladeshi migrants through southern Thailand, after successive Thai governments largely ignored the brutal trade.
People-smugglers abandoned thousands of migrants at sea or in jungle camps after a Thai clampdown on the multi-million industry in May, a crisis that eventually forced a belated Southeast Asia-wide response.
Arrest warrants have now been issued for "four military officers - three from the army and one in the navy", Paween Pongsiri, a southern deputy regional commander, told AFP.
This number includes Lieutenant-General Manas, with Paween declining to name the others.
Manas is accused of being a major kingpin in the lucrative human trafficking and smuggling trade.
Most migrants sought a new life in Malaysia, but many found themselves held captive in dismal camps on both sides of the Thai-Malay border - or on boats - until relatives stumped up ransoms.
Manas's alleged involvement raised awkward questions for junta chief Prayut Chan-o-cha, who has repeatedly justified his coup last year as a much-needed antidote to graft that he says flourished under a series of elected civilian governments.
Manas was promoted while Prayut was army chief.
While rights groups welcomed his arrest, they said it was unlikely such an influential officer would have acted alone.
Paween added that a total of 153 warrants have been issued for trafficking since the crackdown, with 90 people detained so far. At least 72 have been indicted with no trials yet under way.
Thailand has long been a hub for the trafficking of persecuted Rohingya Muslims from Myanmar, who in recent years have been increasingly joined on their perilous sea crossings by Bangladeshi economic migrants.
The belated Thai crackdown came after the United States last year relegated the kingdom to the bottom rung of an influential report ranking nations on their anti-trafficking efforts.
In July it was was placed in the bottom tier for a second year in a row, alongside nations like Iran, Libya, North Korea and Syria.
On Monday national police chief Somyot Poompanmoung told reporters that 32 policemen including immigration officers in southern provinces have been transferred from their jobs over "involvement in the trafficking of Rohingya" migrants.
