The Malaysian government said it was investigating whether local forestry officials were involved with the people-smuggling gangs believed to be responsible for nearly 140 graves discovered around camps near the Thai border.
The dense forests of southern Thailand and northern Malaysia have been a major stop-off point for smugglers bringing people to South-east Asia by boat from Myanmar - most of them Rohingya Muslims who say they are fleeing persecution - and Bangladesh.
Yesterday, the authorities took a group of journalists to one of the camps, nestled in a gully amid thick jungle.
Apparently abandoned in haste, what remained of the camp was little more than a tangle of bamboo and tarpaulin, but one police official said it could have held up to 400 people.
Digging with hoes and shovels, Malaysian police forensic teams began pulling out the remains of dozens of suspected victims yesterday from the shallow graves.
State news agency Bernama quoted Malaysia's police chief Khalid Abu Bakar as saying that the camps were thought to have been occupied since 2013, and two were "only abandoned between two and three weeks ago".
The Malaysian authorities said on Monday that a special police unit found 139 graves last week around 28 camps scattered along a 50km stretch of the border in the northern state of Perlis.
The unit was acting on information and intelligence gathered following the arrest this year of 37 people suspected of involvment in human trafficking.
Two of the suspects were low-ranking policemen.
The police believe they have found all the camps.
The scale of the discoveries has raised questions about the level of complicity by officials on both sides of the border.
Malaysia's Home Minister Ahmad Zahid Hamidi said yesterday that initial investigations revealed links between forest rangers and smuggling syndicates, Bernama reported, adding that some had been detained by the police as part of the probe.
"We suspect some of them were involved... but we are working with the forestry department in terms of enforcement as they are supposed to carry out enforcement in the area," he was quoted as telling reporters in Parliament.
On Monday evening, the police removed a badly decomposed body found in a shack at one of the camps.
They said the unidentified person had been dead for around two or three weeks.
"The syndicate did not have time to bury the body as they were rushing to leave the camp," Bernama quoted local district police chief Rizani Che Ismail as saying.
The discovery of similar camps and graves in Thailand early this month has led to thousands of Rohingya and Bangladeshi migrants being abandoned by the traffickers to fend for themselves at sea.
The vessels have been landing at parts of Malaysia, Indonesia and Thailand in recent weeks.