The Tunisian Prime Minister Ali Larayedh has blamed the hardline Salafist movement Ansar al-Sharia for the killing of two prominent politicians and several soldiers.
"We have discovered proof that the Ansar group is responsible for the assassinations of Chokri Belaid and Mohamed Brahmi and the attacks at Mount Chaambi," Larayedh told reporters on Tuesday.
The killings of Belaid in February and Brahmi in July plunged Tunisia into political turmoil which political leaders are struggling to resolve. Police said the two politicians were killed with the same gun.
Ansar al-Sharia has also been suspected in the violent attacks in the Mount Chaambi area near the Algerian border, including the killing of eight soldiers last month.
Laradeyh blamed the Salafist movement for liaising with Al-Qaeda's North African affiliate and announced the group as a terrorist group.
Ansar al-Sharia is considered one of the most radical groups that emerged after the secular autocrat Zine al-Abidine Ben Ali was toppled in 2011.
The Ansar leader Saifallah Benahssine, also known as Abu Iyadh, is a former al-Qaeda fighter in Afghanistan sought by police for allegedly inciting an attack on the US embassy in Tunis in September 2012.