TUNIS -- Tunisia's interior minister said on Friday that secular opposition politician Mohamed Brahmi had been killed with the same gun that was used to kill his party leader Chokri Belaid six months ago, suggesting the involvement of the same radical Islamist group.
Brahmi was shot dead on Thursday, setting off violent protests against the Islamist-led government in the capital and elsewhere.
Lotfi Ben Jeddou told a news conference: "The same 9mm automatic weapon that killed Belaid also killed Brahmi."
He named the main suspect as a hardline Salafist, Boubacar Hakim, already being sought on suspicion of smuggling weapons from Libya.
Ben Jeddou said authorities had identified 14 Salafists suspected of involvement in Belaid's assassination, and that most were believed to be members of the local hardline Islamist group Ansar al-Sharia.
Ansar al-Sharia is the most radical Islamist group to emerge in Tunisia since secular dictator Zine al-Abidine Ben Ali was toppled in 2011.
The government is led by a moderate Islamist party, Ennahda, but Salafists are seeking a broader role for religion, alarming a secular elite that sees them as a threat to individual freedoms, women's rights and democracy.
The group's leader, Saifallah Benahssine, also known as Abu Iyadh, fought with al Qaeda in Afghanistan and is wanted by police on suspicion of inciting an attack on the U.S. Embassy in September. Four people were killed in those disturbances, which began as a protest over a film that mocked the Prophet Mohammad.
Belaid's assassination on February 6 sparked the worst wave of protests in Tunisia since its Arab Spring revolution more than two years ago.
Ben Jeddou said there was no evidence of any political party's involvement in Brahmi's assassination.