◆ September 20, 2007, Kaishantun, China: Misty rain all day. We go down to the the Duman (or Tumen) River, passing a border security building. The river bank has been cleared and cemented, and the absolute darkness our only cover.

We spend more than three hours waiting for Kang Chul, the North Korean human trafficker. It is already past 2 a.m. A vague figure appears in the river. That must be him. The infrared camera clearly shows naked human figure, his clothes tied up in a plastic bag. Plowing waves that reach up to his waist, Kang spots us and is with us in less than five minutes.

Wet clothes would draw attention if he got back, hence the nudity. He is crawling up the bank, like a wild animal approaching. The wind on is sharp here, and he is shivering. We take out some winter clothes for him to put on and start filming.

He promised to bring someone, but he is alone. "I was supposed to meet a girl at 10 o'clock tonight in a commander's house. But they've stepped up the raids this fall, so I'm not sure whether they got caught." Ten days' work arranging to witness a person being smuggled across the river has come to nothing.

Kang looks at our disappointed faces and takes a small bag from his mouth. "This is Ppaengkkup." Ppaengkkup is another name for ice. So we have run into anther drug deal instead.

Kang Chul shows the news team a parcel of North Korean-made methamphetamine or "Ppaengkkup."

Where does he get it? There is town called Nampo, where North Korea has a factory that makes. "Some individuals invested a lot of money in it." So this is a homegrown industry? "No," he says, the North Koreans buy the precursor chemicals from China and process them in Nampo. He says a 500 g sample costs approximately 500 yuan or US$70. An officer from Durihana Mission hands over the money. "There is 1 kg of it at my brother's house in Chungjin, that'll cost you $15,000." He wants a bigger deal. "Do many North Korean do drugs?" Kang smiles at my question. "Yeah, I do this a lot with my big brother."

We change the subject. "We just need to tip the border guard 500 yuan," he says. "I have to be back in 30 minutes. I need to be careful about the three-man patrol a little inland from here."

Kang, he later tells us, was discharged from the military a year ago, having made some money in the Army by turning a blind eye to human traffickers. Now he sells drugs and women in affiliation with his former commander. "He brought me to the Duman or Tumen River. Since he is the officer, he sent away two soldiers on some errand. There are two more soldiers every 25-30 yards, so I was hiding in the commander's house to avoid them."

For now, he stuffs the money into his plastic bag. From the river he shouts, "Give me a call in a week. I'll bring women or drugs."

◆ September 25, 2007, Wangching, China: We meet a North Korean refugee, Park Mi-sun, who says she worked on a poppy farm in North Korea. She crossed the border in August 2001 because she didn't get paid for her work at the farm. It is a way for the government to earn dollars, she says.

Every spring, she says the technology training center allocates poppy crop targets for each farm. "You can get only 1 gram of opium out of a bunch, so the target can be easily estimated. The farm was so large that we couldn't see any other crop except poppies for five miles."

Gathering the dark extract from poppy is only for women with children, as it is said to cause infertility. "If you touch your tongue with the hand that touched the extract, you get dizzy and collapse. They're extremely strong," she says.

Poppies are planted in the spring and harvested in the fall. Farmers send the extract to the institute for approval. The buds after extraction are hung beneath the eaves and dried, as a cure-all home remedy. "For a bad case of diarrhea, we make tea from it. We didn't know it was addictive."

But poppy farms near the border are gradually dwindling. Park raises her voice. "It's because the Chinese stepped up the drug raids, so they just moved the farms further inland. It's common for average households to grow poppies; they're everywhere in North Korea."

By Park Jong-in, Lee Hark-joon