Tunisian security forces have killed five heavily armed men in an hours-long firefight after they crossed into the country from Libya with a larger group.

An Interior Ministry statement said that a civilian was killed by a stray bullet and a Tunisian army officer was wounded in Wednesday's exchange of fire. It said the five were killed after taking refuge in a home while an unspecified number of other group members fled.

The ministry said the group entered Tunisia at the Ben Guerdane border post, and the area was quickly surrounded.

It said Tunisian security forces had been placed on alert based on "precise information" on possible border infiltrations following the Feb. 19 U.S. raid on an Islamic State group camp by the Libyan town of Sabratha, near Tunisia.