A rights group says migrants are experiencing widespread harassment and abuse by police as they cross Serbia while trying to reach Western European states.

Human Rights Watch said in its report released Wednesday that thousands of people fleeing Afghanistan, Syria and other violence-ravaged countries in Asia and Africa have been targets of assaults, threats, insults and extortion as they pass through Serbia on their way to the border with Hungary where they try to sneak into the European Union.

HRW researcher Emina Cerovic says "Serbian authorities should be protecting asylum seekers and immigrants, including children fleeing war and persecution, not allowing the police to victimize them."

The police denied the accusations Wednesday, saying the migrants have not complained to the Serbian authorities.