A total of 17 Houthi militants were killed when attempting to infiltrate into a military camp in the government-controlled province of Marib in central Yemen, a military source on the frontline said on Monday.

The operation happened late on Sunday night in Madghal district in the northwestern part of the province.

"Two groups of Houthi militants tried to infiltrate into the camp from two directions despite the truce," the source said on condition of anonymity.

The government media outlets reported the militia's attack in Madghal, without providing further details.

The oil-rich province of Marib has been under government control since the Yemeni civil war broke out in late 2014, when the Iran-backed Houthi militia stormed several northern provinces and forced the Saudi-backed Yemeni government out of the capital Sanaa.

The ongoing truce brokered by the United Nations between the Yemeni government and Houthis has been largely held. It went into force for the first time on April 2 and was renewed for two months on June 2, and then extended for an additional two months on Aug. 2.