A former president of the Rohingya club in Thailand has alleged that Malaysia is housing some 80% of the holding camps where young Bangladeshi and Rohingya migrants are kept.
Abdul Kalam alleged that Malaysians are also directly involved in the trafficking syndicate.
Kalam works with Thai police as a translator when Myanmar refugees are rescued.
"The slave trafficking camps near the Thai border typically house between 500 and 1,000 people," The Straits Times quoted Kalam.
However, Kedah police chief Senior Deputy Comm Datuk Zamri Yahya refuted allegations that such camps exist on the Malaysian side of the border.
More than 100 suspected migrants from Bangladesh and Myanmar have been found in Thailand's southern Songkhla province, Thai police said on Friday.
On May 2, police exhumed 26 bodies from a mass grave in the Sadao district in Songkhla province. All are believed to be migrants from Myanmar and Bangladesh.
The discovery of the large camp, hidden deep in the jungle, came this week with the arrest of a trafficker named Anwar, who is thought to be one of southern Thailand's most significant traffickers.