Speed boats ferry people to shore from a giant ship hovering off the coast after the ransom is paid – and those who die onboard are simply tipped over the side.
“One boat, maybe two,” said Commander Zainol Ahmad, as we watched him conduct his crew from the bridge of the Malaysian warship KD Lekir.
The 22,000 tonne Corvette swung round to the north and members of Commander Ahmad’s team aimed their binoculars in the direction of the maritime border with Thailand.
They had just received a tip about “suspicious vessels” with passengers crowded on the top deck and the crew were keen to check it out.
Such activity represents a major change for the Malaysians.
Earlier this month, naval units pushed the migrants’ boats back to sea but after a storm of protest, both at home and overseas, the government committed itself to assisting them, including an offer to provide them with temporary shelter – and the UN and others say the demand is great.
It is thought that there are well over 2,500 people adrift on the Andaman Sea, with little to eat or drink.
Back on the warship, we spent hours trawling up and down a section of ocean referred as “F Sector” but the migrants’ boats never appeared.
As we headed back to port, crew members told us they thought the boats were “hiding behind an island on the Thai side”.
And that seemed odd. Why were migrants, who have been at sea for months and were in desperate need of food, water and fuel, hiding from people intent on rescuing them?
There is only one possible explanation. The brokers and the human traffickers are back in business.
Several weeks ago, Thai police discovered a number of inter-connected camps strung along the Malaysian border, where tens of thousands of Burmese Muslims and Bangladeshis were brought by boat.
In order to win their release from these jungle prisons, relatives were forced to pay a “ransom” of $2,000 to $3,000.
Many more camps have since been discovered – you can see our visit to one of these shocking facilities here – but Channel 4 News has learnt that the authorities’ crackdown has not put the traffickers out of business. Instead, they are adapting their operations, by moving the camps offshore.
Abdul Kallam, a key member of the Rohingya community in Thailand and advisor to the police on human trafficking, says criminal gangs are now operating from an old fuel tanker which sails in international waters.
“It has been out there for two months now and it’s moving all the time. The ship has got 2,000 people on it.”
He says speed boats ferry people to shore after the ransom is paid and those who die on the ship from illness or abuse from the guards are simply tipped over the side.
“The traffickers have moved the jungle camps out to sea so the police have to investigate the gangs on land and on the water,” he says.
“The human trafficking trade has huge money involved, it is not small business. It is massive.”
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