A Hungarian appeals court has lowered to five years from seven the prison sentence of a Syrian man convicted of entering Hungary illegally and of complicity in throwing rocks at police during a 2015 border riot.

The case stems from rioting at the Hungary-Serbia border on Sept. 16, 2015, when dozens of police officers, migrants and some journalists were injured in clashes a day after Hungary closed the frontier, stranding hundreds of migrants.

Amnesty International said the “absurd” conviction exemplified “the erosion of the rule of law and human rights protections in Hungary.”

The appeals court in the southern city of Szeged said Thursday that Ahmed Hamed has to serve at least two-thirds of his sentence before he can be released.