Outside an embassy compound in Beijing the security is unusually tight.
We watch as suddenly, three men make a dash for a nearby building.
Some never make it past the fence, others are roughly knocked to the ground and dragged away.
The intruders are North Koreans, their objective is asylum in a foreign embassy.
These people had fled starvation and political repression. Most countries would consider them refugees. But not China.
Unwelcome
"These people do not fall into the category of refugees, but rather, according to us, they are illegal border crossers," says Chinese foreign ministry spokesman Liu Jianchao.
We head for the North Korean border to try and find out why so many are now trying to seek asylum.
We come across a military road block. There are troops here hunting for North Koreans and they don't like being watched.
Our first view of North Korea is green fields, but they are deceptive - in the last 5 years at least one million of its people have died of starvation.
Easy crossing
At the border is the Tumen river, shallow and narrow enough to wade across or in winter - when it freezes over - simply walk across.
That is exactly what tens of thousands of North Korean refugees have been doing.
In a city near the border we visit a safe house run by South Korean missionaries. There are 15 North Koreans here, all preparing for their escape.
Among them is a 15-year-old boy whose parents had both starved to death in the North Korean famine and a young woman sold as a sex slave to a Chinese businessman.
Hopes for a new life
The group in the safe house were all dressed in new clothes, ready for their bid for freedom.
But they never made it. Hours after we interviewed them they were caught trying to board a train for the capital. Soon they will be sent back over the border.
Every one of the North Koreans I meet in north-east China has an appalling tale of woe.
One middle-aged man is so fearful of being sent back, he carries a bag of rat poison to eat if he is caught.
In North Korea, these people suffered misery and starvation.
In China, they can eat, but they have little else - no security and they live in constant fear of being caught and sent back.
Unless that situation changes, the increasingly desperate asylum bids look set to continue.