Danish police say 23 people have been detained for violence after a far-right provocateur tossed a copy of the Quran in the air in an immigrant neighborhood in Copenhagen.

Copenhagen police said Monday the detainees were suspected of being behind dozens of arson fires of cars and garbage containers mainly in Noerrebro, an immigrant district in the Danish capital.

The unrest started after Rasmus Paludan, a lawyer who cites freedom of speech rights as he stages demonstrations across Denmark under heavy police protection, threw Islam's holy book in the air several times in Noerrebro.

Danish Prime Minister Lars Loekke Rasmussen called Paludan's demonstration "a meaningless provocation."