As the trade in human beings becomes more and more profitable, the BBC's Jonathan Head discovers that entire communities in Thailand are helping the traffickers.
Earlier this month, I accompanied a group of Thai volunteers through the steamy mangrove forest of an island on the Andaman coast. They were following up hazy reports of unmarked graves on the island; it was known to have been used by traffickers to hold large groups of migrants while they waited for transport south towards the Malaysian border.
They dug down deep into the waterlogged soil, before the first fragments of bone appeared. Then they pulled at a soggy wet cloth. It was a dress. Inside were the yellowing bones of a woman. Who she was, or how she died, we still do not know. But it is almost certain she was one of the migrants.
She must have endured a gruelling sea journey to reach this desolate spot. Had she lived, the ordeal ahead of her, on her route to a better life in Malaysia, might have been even worse.