Thai authorities have arrested 65 suspects out of 119 wanted for human trafficking of Rohingya migrants since May, but experts warned that more needs to be done to stamp out the trafficking network responsible for the “death camps” discovered in southern Thailand and Malaysia.

A Thai police officer who works in southern Thailand and wanted to remain anonymous said he feared the traffickers may change tactics from transporting migrants in large numbers, to trafficking them in small groups or even one-by-one.