By Afra Aksoy

MAARIB, Yemen

Thirteen Houthi rebels were killed Tuesday in clashes with government forces in central Yemen, according to the military information center.

The clashes broke out after government forces repelled a rebel attack on military positions in al-Malagim district in central al-Bayda province.

Al-Bayda province has been witnessing battles between army units and Houthis over the last few months.

Yemen has been wracked by violence and chaos since 2014, when Shia Houthi rebels overran much of the country including the capital, Sanaa.

The conflict escalated in 2015 when Saudi Arabia and its Sunni-Arab allies -- who accuse the Houthis of serving as an Iranian proxy force -- launched a massive air campaign in Yemen aimed at rolling back Houthi gains.

The ongoing violence has devastated basic services in Yemen, including water and sanitation systems, prompting the UN to describe the situation as one of "the worst humanitarian disasters of modern times".