Slain Tunisian politician Chokri Belaid.

TUNIS — Jihadists who have since joined the “Islamic State” group claimed the 2013 murders of two secular politicians that plunged Tunisia into crisis, warning of more killings just days before a presidential runoff election.

“Yes, tyrants, we’re the ones who killed Chokri Belaid and Mohammed Brahmi,” Abu Mouqatel, a dual French and Tunisian national wanted for their murders, said in a video released on the Internet on Thursday.

“We are going to come back and kill several of you. You will not have a quiet life until Tunisia implements Islamic law,” added the militant, whose real name is Abu Bakr al-Hakim.

Abu Mouqatel appeared along with three other militants, all of them dressed in combat uniform and carrying arms, with jihadist banners waving behind them. It was not clear where the video was filmed, but Abu Mouqatel claimed they were in an area under the control of IS, which has seized swathes of Syria and Iraq.

“Our message to the tyrants of Tunisia and to their soldiers is this – between us there will (only) be weapons.”

Interior ministry spokesman Mohammed Ali Aroui responded by saying, “Tunisians are stronger than these terrorists. They mean nothing to us.”

Abu Mouqatel, born in Paris in 1983, is considered to be one of the key people organizing the flow of foreign jihadists to Iraq, where he himself has traveled to fight. He was jailed in France for seven years in 2008, but given early release in 2011.

The authorities in Tunisia estimate that as many as 3,000 nationals have gone to Iraq and Syria to fight with jihadist groups, and have expressed concern that some will return to carry out attacks at home.

Belaid was killed on Feb. 6 last year, while Brahmi was murdered on July 25, in attacks that had not previously been claimed, but that authorities had blamed on the jihadist Ansar al-Sharia group.

The killing of Belaid triggered deadly protests and a political crisis that brought down moderate Islamist Prime Minister Hamadi Jebali.