TUNIS Police in a provincial city in Tunisia used tear gas late on Saturday to disperse hundreds of youths who smashed shop windows and damaged cars, witnesses told Reuters.
There was no immediate comment from officials on the disturbances. Riots are extremely rare for Tunisia, a north African country of about 10 million people which is one of the most prosperous and stable in the region.
Witnesses said several hundred youths gathered in the city of Sidi Bouzid, about 200 km (125 miles) south-west of the capital Tunis, late on Saturday.
They were angered by an incident where a young man, Mohamed Bouazizi, had set fire to himself in protest after police confiscated the fruit and vegetables he was selling from a street stall, the witnesses said.
"The violent clashes ended with the arrest of scores of people," a witness, who requested anonymity, told Reuters. "(There was) breaking of shop windows and smashing of cars, while police fired tear gas."
Another witness, a relative of the man who set fire to himself, said outbreaks of rioting had continued into Sunday.
"People are angry at the case of Mohamed and the deterioration of unemployment in the region," said Mahdi Said Horchani. "Regional authorities have promised to intervene."
He said Bouazizi was in a critical condition and had been transferred to a hospital in Tunis.
Footage posted on the Facebook social network site showed several hundred protesters outside the regional government headquarters, with lines of police blocking them from getting closer to the building. It did not show any violence.
Witnesses said hundreds of extra security forces had been brought into Sidi Bouzid on Sunday and had established a heavy presence on the streets.
Calls placed by Reuters seeking comment from Tunisian officials went unanswered on Sunday.