Radio and television reports also identified the early morning attackers in the coastal town of Hergla as followers of an ultraconservative strand of Islam known as Salafis. They were seeking to free one of their members who had been arrested for several crimes, according to the report by the state news agency.
It said the attackers were armed with sticks and stones, and they suffered all the casualties, including the 23-year-old who was killed. Police responded with tear gas and warning shots, and said the young man who died was hit by a stray bullet.
The attack follows an incident Wednesday at a high school near the capital, Tunis, during which three men severely beat the principal and destroyed his car, allegedly because of he refused to allow a student to enter wearing the face-covering veil of the ultraconservatives.
Tunisians overthrew their secular dictatorship in 2011, in an uprising that sparked pro-democracy movements around the region, and since then there has been a surge of religious sentiment.
Some groups, loosely described as Salafis by the media, have been aggressive in trying to push their more conservative views on society, attacking art exhibits, cinemas and liquor stores. A group of Salafis attacked the U.S. Embassy on Sept. 14, destroying a nearby American school.
The wave of arrests that followed the incident, however, saw a dramatic drop in attacks by Salafis.
Tunisia's economy has suffered since the revolution, and nearly a third of young people are unemployed, prompting some to join extremist groups. Observers also say criminals have adopted the Salafi label as a cover for their activities.