The report, in particular, will contain separate cases of maltreatment and humiliation at the hands of police in Hungary, Bulgaria, Croatia and other states, and demand from these states to uphold human rights standards, according to the media outlet.
Th so-called Balkan route is used by hundreds of thousands of asylum seekers from the Middle East and North Africa to escape from hostilities in their countries and reach wealthier EU states.
The Balkan states have opposed EU position on immigration, in particular, over the migrants quota system adopted in September 2015 that envisages the relocation of 160,000 asylum seekers across the bloc within two years.
Bulgaria has said in the past it is prepared to close its borders to refugees, with the prime minister stressing he will not let his country become a buffer zone for millions of migrants. Hungary has also expressed opposition to the EU quota scheme, building fences to prevent more refugees from into its territory.