More than a dozen government-aligned fighters were killed in western Yemen Thursday after Iran-backed Houthi forces launched a deadly offensive against the internationally recognized government, marking the latest escalation in the protracted conflict that's drawn in regional heavyweights. 

What happened: At least 13 members of the government forces were killed in clashes with the Houthis, Agence France-Presse reported, citing military sources. Most were killed along the front line between the Red Sea port city of Mocha and the inland city of Taiz, while the others were killed closer to the coast.

Taiz, located about 80 kilometers (50 miles) east of the Red Sea, is held by the Saudi-backed government but largely surrounded by Houthi-controlled territory.

Yemen’s Army Media Center said the Houthis launched an offensive against military positions in the Maqbana mountains and attempted to advance into several areas west of Taiz. The government-aligned National Resistance Force, which is based along Yemen’s western coast, said its fighters engaged in “fierce clashes” with the group.