THE death toll from clashes between Tunisian forces and extremist attackers near the Libyan border has risen to 55, according to the country's prime minister Habid Essid.
Mr Essid said 36 attackers, seven civilians and 12 members of Tunisia's security forces died and 17 others were injured.
No group claimed immediate responsibility for Monday's attack in the city of Ben Guerdane.
Mr Essid told a press conference on Tuesday that about 50 gunmen - most of them Tunisians - took part in the attack.
He said the gunmen targeted a police station and military facilities in Ben Guerdane after launching their attack from a nearby mosque.
He added that seven attackers were arrested and gave information that led to the discovery of a weapons cache.
Mr Essid told the press conference: "The attack that happened yesterday showed that our military and security forces were ready.
"We won a battle, but we haven't yet won the war on terror, and that war continues."
He also confirmed that the chief of the anti-terrorism brigade in Ben Guerdane was among those killed. He was killed in his house when he was preparing to go to work, at the beginning of the attack.
Websites affiliated with Islamic State said IS militants were handed a tough blow by Tunisian security forces. One site published more than 30 pictures showing militants' bodies as well as weapons and munitions seized.
Tunisia is especially worried about the IS presence in Libya after dozens of tourists were killed in attacks in Tunisia last year. IS extremists claimed responsibility for those attacks, and Tunisian authorities said the attackers had been trained in Libya.
Last week, Tunisian security forces killed five heavily armed men in an hours-long gunfight after they crossed into the country from Libya with a larger group. Tunisian security forces had been placed on alert based on "precise information" of possible border infiltrations following a February 19 US raid on an IS camp near the Libyan town of Sabratha, not far from the Tunisian border.
A jihadist wrote on an IS-affiliated website that the gunmen in Ben Guerdane were part of a group that withdrew from Libya because "they were under big pressure, live in a difficult situation and being sought after by everyone especially after last month's US air strike".
