Dramatic testimony from escaped prisoners has revealed how the Burmese army is forcing convicts to serve as porters on the frontlines in fighting against ethnic tribes.
Prisoners have been tortured, used as human triggers for landmines and - in some cases - summarily executed, say human-rights groups.
Plucked from Burma's crowded jails across the country, the prisoners are driven to operations in the east where troops are battling ethnic Karen rebels, who have opposed the state since its independence in 1948.
"We were carrying food up to the camp and one porter stepped on a mine and lost his leg," one prisoner, who subsequently escaped, told rights activists.
"The soldiers left him; he was screaming but no one helped. When we came down the mountain he was dead. I looked up and saw bits of his clothing in the trees and parts of his leg in a tree."
Another prisoner forced to carry supplies told about being shot after he and a group of 15 other prisoners ran away from the battlefield.
The prisoner, who used a fictitious name, said: "The soldiers told us at night that there was a lot of fighting on the mountain and that if we were alive tomorrow night we would be lucky. We heard the [soldiers] yell, 'Don't run, don't run'. I turned around to look and was hit with the first shot ... the bullet hit my right shoulder and broke my arm. It knocked me down on to the ground."
The testimony is included in a report compiled by Human Rights Watch (HRW) and the Karen Human Rights Group.
The report, Dead Men Walking, is based on interviews with almost 60 prisoners who have escaped from forced labour since 2010.
"Convict porters are the Burmese army's disposable human pack mules. Press-ganging prisoners into deadly front-line service raises the Burmese Army's cruelty to new levels," Elaine Pearson, of HRW, said.
In the general hospital of Mae Sot on the Thai-Burma border, the wards are busy because of the war in the mountains. The scarred and bandaged spill into the corridors.
Virtually all of them are here because of landmines.