Human Rights Watch is blasting what it calls Thailand's “arbitrary” policies toward refugees that it says leave thousands vulnerable to arrest and deportation.

In a report Thursday, the rights monitoring group documented Thailand's treatment of the estimated 140,000 refugees bunched in camps along Thailand's border with Burma.

The report said refugees living within the remote and often overcrowded camps are not able to move freely, earn income, or obtain a quality education for their children.

It says those living outside the camps fare worse, and are subject to arrest and immediate deportation unless they go through an “expensive, difficult, and often corrupt” process of obtaining migrant worker status.

The report described how Thai authorities sometimes require those found outside the camps to serve as forced labor or detain them indefinitely to exact large bribes from their families.

The group is urging Thailand to work with the United Nations to establish a “fair and transparent” refugee screening system for the 40 percent of Burmese refugees it says remain unregistered.

It also wants the government to come up with a plan on how to best allow the safe return of Burmese refugees once violence in their homeland has subsided.

Thailand, which has not signed the 1951 U.N. Refugee Convention, does not have a refugee law or functioning asylum procedures.