Insight - As fighters return from Libya, Tunisia faces growing challenge

BEN GUERDANE, Tunisia (Reuters) - After a U.S. air strike killed a Tunisian jihadist commander in western Libya in late February, dozens of Islamic State fighters sneaked across the border into Tunisia and attacked an army barracks and police bases in the town of Ben Guerdane.

In the battle that followed, Islamic State militants shot dead local Tunisian anti-terrorism chief Colonel Abdel Atti Abdelkabir metres from his home. Residents, including the colonel's brother, say they recognised some of the attackers as former neighbours and classmates who had left to train with Islamic State in Libya. In all, more than 50 militants died in the assault.