Libyan officials say Islamic State militants have killed at least three troops in an attack on a checkpoint in a desert town.

A statement by the self-styled Libyan National Army said the militants captured four soldiers in the attack at the town of Zallah Saturday, but troops were able to free three of them.

The Islamic State group claimed the attack.

The extremist group expanded its reach in Libya after the country was plunged into chaos following the 2011 uprising that ousted and killed Moammar Gadhafi.

Zallah is about 750 kilometers (466 miles) southeast of the capital, Tripoli, where Field Marshal Khalifa Hifter's LNA forces are currently fighting to take control of the city from militias affiliated with a weak U.N.-supported government.