KACHIN STATE, MYANMAR - The clanking sound of leg irons shackled around the ankles of the unwilling patients signals the arrival of a small group of heroin addicts at the mess hall located inside a fortified Pat Ja San compound near Laiza in Myanmar's Kachin state, located in the country's north along the border with China.
The compound is one of 28 run in Kachin and neighboring Shan state by Pat Ja San, a Christian anti-drug vigilante group.
International observers say treatments at the rehabilitation centers are rudimentary and brutal compared to modern Western methods. The detoxification program often includes locking patients in barred rooms and confining their legs to wooden stocks to prevent escape during the initial treatment when addicts experience the painful effects of withdrawal.
Methadone is sometimes available, but medical training for the workers and access to modern drugs are limited, especially in the rural areas where military battles persist.
'Drug is everywhere'
Lahtaw Ah Li, 22, is a new arrival. At 14, he began working at a jade mine in Hpakant township in Kachin state, where most of the industry is concentrated, scavenging through discarded rock piles for bits of the valuable gem. A few years later, he started using heroin to cope with the long hours.
"The drug is for sale everywhere around the mine sites, and it's cheap to buy," Ah Li said about heroin, which costs about 75 cents per injection.
Drug camps, or "shooting galleries," are openly set up in the mining areas, supplying users with syringes and cheap heroin to inject or inhale.
Corruption is rife in the region. Some law and mining officials illegally distribute the drug, which is largely smuggled in from neighboring Shan state, according to the Burma Campaign UK.
After his family persuaded him to return to the rehabilitation camp for internal refugees near Laiza where they lived, Ah Li kept using the drug until he tested positive during a roadside stop run by the Pat Ja San. Most checkpoints in Kachin have an outhouse or hut where urine samples are taken immediately.
"I only use drugs while I'm working at the jade mine and searching for jade," Ah Li said.
In 2012, renewed fighting between Myanmar's military and the Kachin Independence Army forced Ah Li and his family from their village near Laiza in Kachin state. The KIA is one of the ethnic armies battling Myanmar's military in conflicts in several parts of the country over autonomy and control of resources.
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For fellow patient Seng Nu Pan, treatment at Pat Ja San is not her first time.
Trouble began for her in 2011, when her mother had to close the family's market stall after fighting resumed in Waimo township in Kachin state. Her mother crossed over into China to find work, while Nu Pan began selling heroin and subsequently started using the drug herself.
Two years ago, her family demanded she enter a Pat Ja San rehabilitation center, where she kicked the habit. This time after a relapse, she returned voluntarily.
Je Yang camp
In the nearby Je Yang camp for internal refugees - the largest of 138 such camps in the state - economic instability and the hardships of war have left some civilians turning to drugs as a coping mechanism.
For those working outside the camps, heroin and amphetamines are readily available because of increased production by organized crime gangs and armed militia groups, including those allied with the Myanmar military. Amphetamine addiction is also on the rise.
Pat Ja San drug prevention volunteer Lahtaw Gum Ja has been based at the Je Yang camp since it was formed in 2011.
The former community leader is a father and is concerned that the younger generation will get hooked on the drugs.
Suspected users in the camps are made to provide urine tests, and if they fail, they are locked up and forced to attend a Pat Ja San rehabilitation center.
"We lived in the IDP camp near the China border, and there are many drug dealers and users along the border," Gum Ja said, as he prepared a batch of testing kits at the camp office.
"When we hear of people in the IDP camps addicted to drugs, we will investigate and find out who is using it, and we will have the leaders of that section in the camp find the person and take them to the rehab center."
Most of the precursors for methamphetamine production are supplied through China, which some observers say is a driving force behind the production.
"China's role as both a distribution path and a market for Myanmar's illicit drugs really should not be underestimated," Phil Robertson, deputy director of the Asia Division of Human Rights Watch, said.
"Demand for drugs continues to fuel the presence of armed groups in the parts of northern Myanmar where growing is taking place, and accompanying violence connected to the drug trade frequently falls heaviest on vulnerable civilians."
As Myanmar's internal conflicts continue, fueled by battles for profitable natural resources and large-scale development projects, the drug crisis is expected to continue.
"Expanding real drug treatment programs that are easily accessible and community-based would be the best way to curtain drug addiction," Robertson said. "Treatments need to be rights-respecting and voluntarily entered into by the person to be treated.