ATHENS - Unrest erupted in an Athens prison on Sunday evening, when dozens of inmates refused to return to their cells following a Muslim protest against an American film on Prophet Mohammed, local media reported.

According to the reports, no injuries or extensive material damage have been reported.

Police sources confirmed that disturbance at Korydallos jail started when a group of Muslim detainees launched a protest, setting sheets on fire at the yard, while chanting anti-American slogans.

A few hours earlier about 700 Muslims had marched in the center of Athens against the "anti-Islam" film, clashing briefly with police.

According to Greek media reports, prisoners who joined Muslim inmates were protesting against overcrowding and budget cuts in prisons in debt-crippled Greece.

Anti-riot police forces have been deployed in the area to assist prison guards if inmates culminate the protest overnight.

The US-made controversial film "Innocence of Muslims", which is deemed by Muslims as an insult to their Prophet Mohammed, triggered widespread protests in some Muslim countries.