One man was killed at a demonstration on Sunday when soldiers fired into the air to bring the crowd under control. It was the first reported death in a number of violent protests that have hit Tunis and other cities since Friday.

Prime Minister Beji Caid Sebsi said the protests were intended to spread chaos and derail plans for an election on Oct. 23 that will choose an assembly charged with drawing up a new constitution.

“There is an orchestrated plan to upset the stability of the country,” he said in a televised address.

“Elections will be held as scheduled on Oct. 23 despite everything,” he said. “I appeal to all political parties and citizens to defend the country.”

The Defense Ministry said the demonstrator had been killed in Sidi Bouzid, the town in central Tunisia where a young man killed himself by setting himself on fire last December, providing the spark that set off the Arab Spring revolutions now convulsing much of the region.

“One civilian was killed yesterday evening in Sidi Bouzid when soldiers fired into the air to disperse rioters who had attacked them,” Col. Marouan Bouguerra told journalists in Tunis on Monday.

The rioting is the starkest sign to date of the friction between Tunisia’s secular establishment and conservatives who have been growing more assertive since the country’s leader Zine Al-Abidine Ben Ali was ousted in a revolution six months ago.

Sunday’s violence was sparked by an incident on Friday when police, trying to break up an anti-government demonstration in the center of Tunis, fired teargas inside a mosque.

In the town of Menzel Bourguiba, about 70 km north of Tunis, four police officers were wounded in clashes with rioters, said a police source.