A Tunisian police officer has been killed on Wenesday near beach resort of Sousse, where a gunman killed 38 people in June, a security source said.
Tunisia is striving to protect its vital tourism centres particularly the Bardo Museum and beach resort of Sousse after attacks on the sites in March and June.
“Two young men on a motorbike opened fire on the police. At least one police officer is dead ,” the security source said.
The Interior Ministry said that police in the city, 140km (90 miles) south of the capital Tunis, have launched a vast search for the millitants.
Since its 2011 uprising ousted autocrat Zine El Abidine Ben Ali, Tunisia has emerged as a model for democratic transition in the Middle East, however, the North African state has also struggled with a rising militant threat.
Officials say more than 3,000 Tunisians have left to fight in Iraq and Syria and increasingly in neighbouring Libya, where the chaos generated by a battle between two rival governments has left a security vacuum for warring groups to grow.
The gunmen in the Sousse attack and the Bardo Museum were trained in militant camps in Libya, but officials and families say they were indoctrinated by radical groups at home.