“A total of 937 people are in custody” after acts of violence, theft or vandalism, interior ministry spokesman Khlifa Chibani told AFP.
On Sunday, the North African country marked the anniversary of the 2011 uprising that gave birth to the Arab Spring.
Chibani said 41 people aged between 13 and 19 were detained on Sunday amid fresh protests.
The authorities say that in a week of clashes, 105 members of the security forces were injured, but no record of the number of protesters injured was available.
One protester died last Monday in circumstances that remain unclear.
The results of an autopsy due to be released last Thursday have not yet been made public.
Minor incidents including youths burning tyres were reported overnight Sunday-Monday in two Tunis suburbs, media reports said.
The North African country is seen as having had a relatively smooth democratic transition since the January 14, 2011 toppling of President Zine El Abidine Ben Ali after 23 years in power.
But anger has risen over new austerity measures after a year of rising prices, with protesters on Sunday again chanting the 2011 slogans of “Work, Freedom, Dignity”.
Tunisia’s 2011 revolt was sparked by the self-immolation of a fruit seller in desperation at police harassment and unemployment.
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