Malaysian police said on Sunday they had found 24 human skeletons - all believed to be victims of trafficking - in newly discovered graves along the Thai border in the northern Malaysian state of Perlis.

The latest gruesome discovery comes after police found 139 graves and 28 abandoned “detention” camps capable of housing hundreds of people in May, laying bare the grim extent of the region’s migrant crisis.

The new graves were found on Saturday near the peak of a hill surrounded by jungle terrain and along the Thai border, not too far from the graves unearthed in May, Perlis police chief Shafie Ismail was quoted as saying by Bernama, the country’s official news agency.

“It is believed that heavy rain had eroded the graves,” he said.

After May’s unearthing, the remains of 106 people were exhumed, mostly believed to be Muslim Rohingya fleeing persecution in Myanmar, as well as Bangladeshis seeking better opportunities abroad.

Mass graves were also discovered on the Thai side of the border.

The Rohingya, a Muslim minority from Myanmar, have for years sought to escape what they say is worsening persecution by the country’s Buddhist majority.

Fleeing abroad by the thousands each year, they typically put their lives in the hands of often brutal smugglers and traffickers who arrange a perilous passage by sea and land, usually destined for Muslim-majority Malaysia.