Nearby villagers said four such camps were being operated near the village of Ban Chalung in Songkhla province. It is not clear whether they are being operated with the approval of the Thai government, and it is not known how many people are held in the camps in total.

The 's sources include two Rohingya men who said they had escaped from the camps, as well as people with connections to brokers, who pay Thai immigration officers at least 10,000 baht (HK$2,400) for each Rohingya. The brokers then try to sell them to their relatives in Malaysia for up to 60,000 baht, the sources said.

One of the escapees, "A", led a reporter through steep jungle to reach the perimeter of a camp on Friday. Although caution prevented them from emerging through the undergrowth to take a clear photo of the camp - which villagers said was protected by armed guards - they were close enough to hear people loudly speaking the Rohingya language.

Thais could also be heard, giving instructions to each other.

"A" said he escaped in late November. Since then he has been sheltered by villagers who found him in the jungle and corroborated parts of his story.

In the 14 days he was held at the camp, "A" said that 16 people had died. Some had fallen ill during long periods in detention without medical care. "People are forced to scramble for food because there is just one meal a day. People are given a half glass of water in the morning and another half glass each evening," he said.

"I was shocked in the camp to see Rohingya women raped by other prisoners. Conditions are so primitive. It becomes a struggle for every person to survive."

The second escapee, "J", told of a journey that began when he fled Myanmar for Bangladesh two years ago. Then, in November last year, he caught a boat to Thailand, which was intercepted by a Thai military vessel and uniformed authorities.

That camp was then raided in January by different members of the Thai military, who he presumed to be members of the army. "J" and fellow detainees were transferred into formal Thai custody in Padang Besar on the Malaysian border and assured that they would eventually be sent back to Myanmar or resettled in a third country.

"[But] two months ago, 40 in my cell were taken away. I think they ended up in Malaysia. One of them called back and said … 'Do not believe that Immigration is going to send you back to Myanmar or send you to a third country. They will sell you to a broker'."

He was eventually transferred to an immigration centre in northern Ranong, but instead of being deported was then smuggled to one of the secret camps. He fled after five days. "J" was also sheltered by Thai villagers, who introduced him to the 's special correspondent. He named Rohingya brokers Serrif, Ayadul Lao and Yamar as being involved in running the camp.

Colonel Thanakrit Promdonchart, Superintendent of Padang Besar Immigration, said yesterday: "All Rohingya in cells in Padang Besar have been transferred to Ranong Immigration [on the Thai-Myanmar border]. We have to follow the policy of the government. Ask the government in Bangkok for details."

Colonel Eakkorn Bhudsasabordin, Superintendent of Ranong Immigration, said: "About the Rohingya, my commander in Bangkok says we are not permitted to provide information to the media because this is an issue of national stability. My apologies."

Phil Robertson, a spokesman for Human Rights Watch, said that despite Thailand's perennial complaints about the burden imposed by Rohingya refugees, "the reality is quite different since other officials have been all too happy to take advantage of the situation to enrich themselves by facilitating the movement of Rohingya to Malaysia".

He said that almost 2,000 Rohingya who had been given protected status by Thailand and held in immigration detention "are just about all gone - they have been so-called 'soft deported' into the hands of people smugglers and human traffickers who hold them in jungle camps, mistreat and abuse them".

"A" said that escapees who were recaptured were always beaten, and at least one man died as a result. But in late November, "A" made a break for it when the camp flooded.

"There was a big rain and a flood. Eight of us decided to make a run for it. One man fell on the hillside, but we kept running. I was barefoot, like everyone, and I stood on a wooden spike. They left me behind," he said.

"I kept moving through the next day and evening until I met a man in the hillside."

Fortunately, the man turned out to be a Muslim who recognised his plight, in spite of the language barrier, and decided to help him. Today, "A" remains in the care of local villagers, although he hopes to travel to Bangkok where he has located a distant relative.

Local residents near the camp said that vehicles often move people in and out of the site, deep in jungle not far from the city of Hat Yai.

In another village, "J" said that his first stint in formal Thai detention began on January 9 when troops he took to be members of the Thai army raided the smugglers' camp where he was being held.

"Thai authorities held us near a mosque for a month and we were treated well by officials and the locals," "J" said. "After that, we were transferred to Padang Besar Immigration. There were three cells. I was upstairs in a cell with about 80 others.

"We were told by a translator that we would be held for six months, then be sent back to Myanmar or to a third country."

But then he received the telephone warning from a former detainee that a different fate lay in store.

So when his group was told they were being deported, "I decided not to submit", he said. "Two officers handcuffed me and then made me put my thumbprint on a paper by holding down the handcuffs, saying we were going to Myanmar. They wrote the number '56' on my wrist to identify me."

"J" said the group was trucked to the Thai-Myanmar border port of Ranong, loaded on a small boat and taken out to sea.

But it was a ruse. When night fell, the boat simply returned to the same pier and the men were loaded back onto trucks.

"I ended up in Padang Besar, in a camp in the jungle." After five days, he decided to run. He did not stop until he came across a village with a mosque. The locals there have offered to help him start a new life nearby.