Burmese ethnic minority members could face persecution if they are returned home.
Ethnic officials in western Burma say the government must work to end rights abuses.
Cambodia's rights record may worsen under continued rule, rights activists warn.
Cambodia became increasingly restricted in 2010, while several other Asian nations ranked at the bottom of a global freedom index.
Following his two-star general appointment, critics pressure Hun Sen’s son to clean up Cambodia’s military image.
Burma's ruling military junta uses prison labor in its fight against armed ethnic groups.