The Karen don't want to live in government controlled villages (detention camps, actually) because the government forces the Karen to provide free labor to the government for whatever projects are underway. Getting the UN to act is difficult because China has a veto in the security council, and, as in Sudan, is helping the government develop oil and gas fields. But the Burmese government, run by the army since a military coup in 1962, has ignored any outside criticism. Journalists are not allowed to operate freely, and there are heavy restrictions placed on Internet use. The generals changed the name of the country to "Myanmar" in 1989, but many outsiders have ignored that. The generals keep promising that democracy will return, but continue to do what they want. With the exception of the northern tribes, most Burmese just put up with the dictatorship. There has been some rebel activity, but the generals have created a very effective police state. Like Darfur, there does not appear to be any relief insight for the Karen, or any other Burmese who oppose living in a police state.
While the world at least watches the abuse Sudan is inflicting on its own citizens in Darfur, and openly discusses doing something about it in the UN, no such luck for the Burmese being assaulted and killed by their own government. The Burmese government has been waging war on the tribes that inhabit the rugged, and thinly populated, north of the country, for decades. But in the last ten years, it has come down particularly hard on the Karen tribes. Since the 1990s, about half a million people have been driven from their homes, and forced to relocate to areas where the government can better control them. The only other option is stand and fight, which means getting killed, or flee deeper into the jungle. The drill for the last few years is for the army to move in, after the rainy season (June-September), seek out Karen villages, destroy them, and capture or kill any Karen they find. The Karen have learned to flee ahead of the army arriving, then return when the army leaves, rebuild their village, plant some crops, and survive another year. But so far this year, 20,000 Karen have become refugees, as the army kept operating during the rainy season.