Local Sunni Muslim militia ejected Shiite Houthi rebels from much of the southern Yemeni city of Dalea on Monday, residents and combatants said, inflicting the first significant setback on the Iranian-backed rebels in two months of civil war.

Dalea had been a bastion of southern secessionists in Yemen before the Houthis took widespread control of the city in March, after having seized the capital Sanaa in the north in September, toppling President Abed Rabbu Mansour Hadi, and then thrust into the center and south of the Arabian Peninsula country.

After two months of fighting in which much of Dalea has been destroyed, Sunni fighters on Monday turned the tide by seizing a key military base and the main security directorate in the city, militia sources and local residents said. Twelve Sunni fighters and 40 Houthi rebels were killed, they said.