At least 37 undocumented immigrants started a hunger strike in a Sofia prison on Friday to protest their jail sentences for border trespassing, the human rights group the Bulgarian Helsinki Committee (BHC) said.
The inmates, from Algeria, Rwanda, and Syria and other Middle East countries, were initially handed a suspended sentence for entering the country illegally but this was turned into one- and two-year sentences after they tried to leave again.
The BHC said the immigrants came to Bulgaria out of "fear that they would be persecuted in their own countries because of their ethnicity, religion or political views" and argued they should be allowed to apply for refugee status.
In many of the cases, the inmates were not even informed about the motives for their sentences in a language they could understand, the committee also said.
The BHC has long pressed for the decriminalisation of border trespassing, while repeatedly slamming overcrowding, inhumane conditions and widespread abuse in Bulgarian prisons.
On Friday, a prisoner serving a life sentence threatened to jump off the roof of a prison building in the eastern city of Burgas to protest the conditions there.