HUNCHUN, China — The warning came from Kim Jong Un, the North Korean ruler who sees his isolated nation, just across the border from this busy Chinese trading town, as under siege. The attack, he said, must be stopped.
"We must extend the fight against the enemy's ideological and cultural infiltration," Mr. Kim said in an October speech at the headquarters of his immensely powerful internal security service.
Mr. Kim, who became North Korea's supreme leader after the death of his father a year ago, called upon his vast security network to "ruthlessly crush those hostile elements."
Over the past year, Mr. Kim has intensified a border crackdown that has attempted to seal the once-porous 880-mile-long frontier with China, smugglers and analysts say, trying to hold back the onslaught.
The assault that he fears? It's being waged with cheap televisions rigged to receive foreign broadcasts, and with smuggled mobile phones that -- if you can get a Chinese signal along the border -- can call the outside world.
Very often, it arrives in the form of wildly popular South Korean soap operas smuggled in on DVDs or computer thumb drives.
In North Korea, a country where international phone calls and Internet connections exist only for a tiny fraction of a tiny elite, and televisions and radios must be permanently preset to receive only state broadcasts, it's Korean-language TV heartache they crave.
"South Korean dramas, that's what everyone wants," grumbled a Seoul-based Christian missionary who runs a string of safe houses in this part of China, where his network helps people living underground after fleeing North Korea.
One safe house is reserved for traders who sell everything from electronics to shoes inside North Korea -- and who smuggle everything from Bibles to soap operas on the side. He spoke on the condition of anonymity to protect the safety of his network.
There's "Autumn in My Heart," a 12-year-old tear-jerker replete with switched babies, forbidden love and a comatose heroine. And "Stairway to Heaven," an epic of more forbidden love, more switched identities, blindness, insanity, a brain tumor and an evil stepmother.
Everywhere in the soaps, there are tales of unrequited love, conniving rivals and handsome young men who just don't realize they would find true love with the girl next door.
But if it looks absurd -- a Stalinist nation vowing to crush an assault of bad lighting and overacting -- the dilemma is deadly serious for Mr. Kim, who needs to find a way to modernize his country and its economy while holding onto absolute power.
Today, changing technologies, ambitious smugglers and well-funded critics of Pyongyang mean that everything from DVD melodramas to illegal Chinese cellphones to Korean-language radio news broadcasts funded by the U.S. government make their way into North Korea.
Their presence exposes an ever-growing number of North Koreans to the outside world and threatens the underpinnings of the Kim regime.
Mr. Kim's crackdown has been largely aimed at the border with China, long the route for much of the outside information making its way into North Korea, as well as for refugees trying to get out.
Entire border-security units have been replaced inside North Korea, fences have been strengthened, and punishments increased for anyone caught trying to get through, according to smugglers, analysts and Chinese with family ties across the border.
Meanwhile, special security units have been formed to seek out any contraband information or technology that Pyongyang sees as a threat.
"There has definitely been a push to roll back the tide of the flow of information," said Nat Kretchun, associate director of an international consulting group, InterMedia, which released a report earlier this year about information flow into North Korea, based on surveys of hundreds of recent North Korean defectors. The study was commissioned by the U.S. State Department.
Mr. Kretchun's conclusion: North Korea is increasingly anxious to keep information at bay, but has less ability to control it.
People are more willing to watch foreign movies and television programs, talk on illegal mobile phones and tell family and friends about what they are doing, he said.
"There is substantial demand" for things like South Korean movies and television programs, said Mr. Kretchun. "And there are intensely entrepreneurial smugglers who are more than willing to fulfill that demand."
For now, though, times are tough along the border, with smugglers saying North Korean guards have become far stricter about searching for contraband.
In a country where one family has held absolute control for more than 60 years, a communist enclave that survived the downfall of the Soviet Union and a devastating 1990s famine, the notion of allowing knowledge of the larger world is deeply feared.
"Even a hint of illusion or submission to the enemy is the shortest road to death and self-destruction," Mr. Kim said in his October speech, according to the state news agency KCNA.
The enemy works out of places like Hunchun, a brutally cold, money-hungry border town of car-parts shops, cavernous indoor markets piled with shiny polyester clothing and off-brand electronics so cheap it seems almost impossible.
Just a few miles from both North Korea and Russia, it's a town where nearly all signs are in three languages -- Chinese, Korean and Russian -- and where you can find a smuggler in just a few phone calls. Even if they rarely give a name, and are often identified only by their mobile phone numbers.
"Let me worry about how to do it," laughed one smuggler, asked how he gets his goods into North Korea. He is a friendly man, dressed business-casual in black corduroys and a black sweater.
Asked what he could get across the border, he made clear that business was thriving. Televisions, including ones able to pick up foreign stations? No problem. DVD players? Sure. Chinese movies? Yes.
But when asked about South Korean DVDs, the man shifted uncomfortably in his chair. His partner spoke up: No South Korean items -- not DVDs, thumb drives, cosmetics or food.
"Nothing," the partner said firmly.
Soap operas, at first, might not seem like conduits of underground information.
Plenty of other smugglers are willing to carry what the man in Hunchun is not.
Millions of foreign TV and movie recordings are thought to be floating around North Korea, though they are most easily available in cities near the Chinese border.
With the crackdown, analysts say, smugglers appear to have shifted to new techniques, at least for videos: carrying recordings on tiny thumb drives, and then transferring the programs to DVDs inside North Korea.
Because once information starts to flow, information cannot be turned off like a spigot. At most it can be slowed.