A wave of vandalism has continued across Denmark for a seventh consecutive night, officials have said.
Thirteen people were arrested on suspicion of vandalising and torching schools, cars and rubbish containers, with 93 small fires burning overnight, police said.
The unrest - largely in immigrant neighbourhoods - has spread through Copenhagen and across Denmark.
Police are unsure what triggered the violence but some say youths from Denmark's immigrant communities were protesting against perceived police harassment, and suggested Wednesday's reprinting of a cartoon lampooning Mohammed may have aggravated the situation.
"Many people also think it's because the youths are bored," police spokesman Jan Marker said. "We're in the process of putting a profile of these youngsters together to see if we can come up with what is driving them. ... But the only thing we know for sure right now is that most of them are under 18."
Most of the unrest was reported in Copenhagen, particularly in the south-west, Mr Marker said.
Ten buildings were set on fire, of which at least five were schools. Parts of a school in Tingbjerg in Copenhagen was demolished after flames tore through staff rooms and other administrative offices.
"But the general picture is that it looks calmer," Mr Marker said. "It's not as bad as the previous night. It could be because of the arrests we've made."