TUNIS: Four Tunisian police were killed early Wednesday in an attack by suspected Al-Qaeda-linked militants near the Algerian border where Islamists are dug in, with officials vowing a “violent” response.

It was the first deadly assault this year on government forces in Tunisia, where the police and the army have been hunting down jihadis blamed for a string of attacks on security forces.

“A group of 20 terrorists attacked a patrol of the National Guard,” 2 kilometers from Kasserine, which lies at the foot of Mount Chaambi, Interior Ministry spokesman Mohammad Ali Aroui said.

The gunmen opened fire at a police car, killing the four policemen, and fled with their weapons, the spokesman said.

An AFP reporter said the car was riddled with bullets and had overturned by the side of a road in Boulaaba, near Kasserine. The windshield was also shattered.

Aroui said the attackers were members of the Al-Qaeda-linked Okba Ibn Nafaa Brigade, the main Tunisian armed group active along the border with Algeria.

“There will be a severe and violent response,” he added.

A Twitter account close to Okba Ibn Nafaa praised the attack.

“God be praised, a patrol of the pagan [police] was attacked near Mount Chaambi and four [policemen] killed,” the account said.

Okba Ibn Nafaa claimed responsibility for a July 2014 attack that killed 15 soldiers in the Chaambi region in what authorities said was one of the deadliest assaults in the army’s history.

Tunisia has seen a rise in Islamist extremism since the 2011 revolution that ousted veteran strongman Zine al-Abidine Ben Ali.

Dozens of police and military personnel have been killed or wounded in attacks blamed on Islamist militants around the Chaambi range, but also further north along the border with Algeria.

A Tunisian army offensive against the jihadis, who are linked to Al-Qaeda in the Islamic Maghreb, has been underway since 2012 but the ground and air campaign has failed to force them out.

Algerian authorities said soldiers Saturday killed an armed Islamist in the Tebessa region along the northeastern frontier with Tunisia.

Prime Minister Habib Essid, who heads a coalition government that includes moderate Islamists, has said his Cabinet’s priority would be to restore security and “battle against terrorism.”

Tunisia is also fighting against the radicalization of Muslim youth, with authorities saying that as many as 3,000 Tunisians have gone to Iraq to fight in jihadi ranks, including ISIS.