The veteran leader of Tunisia's ruling Islamist party told AFP that the authorites would crack down on hardline Salafists after deadly violence around the US embassy, saying they pose a threat to the country's freedoms and security.
"Each time that parties or groups overstep our freedoms in a flagrant manner, we have to be tough, clamp down and insist on public order," Ennahda chief Rached Ghannouchi told AFP in an interview.
"These people pose a threat not only to Ennahda but to the country's freedoms and security."
Ghannouchi denied that the Ennahda-led coalition government had been lax in its failure so far to arrest Salafist leader Seif Allah Ibn Hussein, suspected of organising the violent protest on Friday of last week at the US embassy and adjacent American school in Tunis.
Now slain Al-Qaeda leader Osama "bin Laden remained at liberty for years without the world's intelligence agencies capturing him, so it's not surpising that someone can go into hiding," he said.
"But the police will hunt him down until he has been arrested."
The Ennadha-led government has come in for strong criticism in the Tunisian press for failing to arrest Ibn Hussein, also known as Abu Iyadh, when he delivered the sermon at a Tunis mosque earlier week.
Ibn Hussein, who heads the extremist Ansar al-Sharia movement, preached at the Al-Fatah mosque in the heart of the capital on Monday surrounded by his followers, and then left, despite a heavy security deployment around the building.
During his sermon, he accused the police of provoking the protesters who attacked the US embassy, and called for the resignation of Interior Minister Ali Latayedh, an Ennahda member.
As fears mounted of fresh violence after the mainly weekly Muslim prayers this Friday, Ghannouchi said that from now on the security forces would deal firmly with any breaches of public order.
"The police have learnt the lesson and I don't think there's going to be any repetition (this Friday)," he said.