People smugglers explore new routes to Malaysia after Thai crackdown-aid groups

A boat carrying Rohingya migrants is pictured off the coast of Thailand in the Andaman Sea on May 14, 2015. - AFP filepic

However, traffickers began diverting migrants to secret camps near the Thai-Malaysia border, holding them for ransom and killing and torturing those whose families could not pay up. Others died of disease and neglect.

After the discovery in May of dozens of graves on the Thai-Malaysia border, smugglers abandoned thousands of migrants at sea to avoid being caught by Thai and Malaysian investigators.

Julia Mayerhofer, interim executive director of the Asia Pacific Refugee Rights Network (APRRN), said the root cause of discontent was still there in Myanmar.

Amnesty International, which released a report on Wednesday about the region's trafficking crisis, pressed Myanmar to stop violence against the Rohingya by state security forces, and to amend its laws to grant the Rohingya citizenship.

"People are still desperate to leave. If you block one way, people will find another way, and that might be more dangerous and more risky for the people," Mayerhofer said.  

(Reporting by Alisa Tang, editing by Belinda Goldsmith and Tim Pearce. Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, corruption and climate change. Visit www.trust.org)