Fresh protests against Tunisia's Islamist-led coalition government erupted on Monday, deepening the north African nation's political crisis as two soldiers killed by militants linked to Al-Qaeda were to be buried.
Police used batons and tear gas against protesters who tried to break into local government offices in the centre-west city of Sidi Bouzid, cradle of the 2011 revolution.
An AFP journalist said security forces also fired warning shots to disperse several dozen people demonstrating against what they called the incompetence of the local governor.
The governor is close to the ruling Islamist Ennahda party.
In addition to being where Tunisia's Arab Spring began in late 2010, Sidi Bouzid was also the home town of opposition MP Mohamed Brahmi, gunned down in the capital on July 25.
Brahmi's was the second political assassination this year, coming after the February murder of Chokri Belaid, also in Tunis.
Many Tunisians blame the government for both killings.
At the end of July, hundreds of protesters tried to block civil servants in Sidi Bouzid from going to work, and police used tear gas against stone-throwing demonstrators.
The demonstrators were then also demanding the dismissal of the governor.
Government detractors say the Ennahda-led cabinet has failed to rein in radical Islamists who have grown in influence and stand accused of a wave of attacks since the 2011 uprising that toppled strongman Zine El Abidine Ben Ali.
An opposition coalition plans another demonstration in Tunis later on Monday, as well as a major night-time protest on Tuesday demanding the government's resignation and the dissolution of the National Constituent Assembly.
Tuesday's protest will also mark six months since Belaid's killing, and is an opposition response to a massive pro-government rally in the capital on Saturday.
Officials have said the same gun was used to kill both Belaid and Brahmi, and pointed the blame at jihadists.
As the political crisis festers, with no immediate way out in sight, security forces are pressing their hunt for militants linked to Al-Qaeda holed up in the rugged Mount Chaambi region near the border with Algeria.
Two soldiers killed when their armoured vehicle was hit by a blast on Sunday were due to be buried on Monday -- one in Sidi Bouzid and the second in Bizerte in the north, the government said.
The military has been hunting the militants since last December, but stepped up its offensive after eight soldiers were killed in an ambush on July 29 and had their throats cut.
On Sunday, Prime Minister Ali Larayedh called on the jihadist militants hiding out near the border to surrender.
"Hand over your arms, turn yourselves in to police, and then police and society will take that into account," he said, quoted by state news agency TAP.
The army has come under a spate of attacks since April and the spokesman said the operation would continue until Islamist militants "are eradicated".
Larayedh, who has already proposed a broader coalition and general elections for December, on Saturday reiterated that his government would not step down, and told a news conference Tunisia needs "national unity".
But dozens of deputies have boycotted the assembly since Brahmi's murder, further delaying the drawing up of a new post-revolution constitution.
The assembly is due to meet on Tuesday morning to discuss the threat facing the country after security forces killed a "terror" suspect in a dawn raid on Sunday.
Interior Minister Lofti Ben Jeddou said that the security forces had also arrested Ezzedine Abdelaoui, who is suspected of involvement in Belaid's murder, during the raid.
Overnight Saturday-Sunday, the interior ministry said police had foiled a new bid to assassinate a political figure and that two "very dangerous terrorists" had been arrested and guns and grenades seized.