A military coalition led by Saudi Arabia has stepped up its attacks on Iranian-supported Houthi rebels in Yemen’s central province of Marib, as its forces draw nearer to the capital San’a.

Since the deaths of 67 coalition soldiers in a Sept. 4 Houthi missile attack in Marib, Riyadh and its mostly Arab allies have escalated their assaults on rebels in the province, according to a coalition member and pro-coalition Yemeni security officials.

Coalition forces now control several installations in the province formerly held by the Houthis and have captured a hill overlooking Marib’s capital, located just 100 miles east of the Yemeni capital, the officials said.

Saudi Arabia and its allies appear to have gained the upper hand in the nearly six-month war since recapturing the southern port of Aden in late July. Since then, they have driven back the Houthis in several southern provinces.

The Saudi-led coalition is fighting to restore the exiled president, Abed Rabbo Mansour Hadi, to power in what has become widely seen in the region as a proxy war between Riyadh and its Sunni Muslim regional allies on the one hand, and mainly Shiite Iran, on the other.

The Houthis adhere to the minority Zaidi offshoot of Shiism. Tehran supports them politically but denies supplying them with arms.

Despite recent coalition gains, Houthi spokesman Nasrudin Amersaid that the Houthis were confident they would prevail in Marib. His forces have destroyed a dozen coalition tanks and 17 armored vehicles, the spokesman said.

"We will keep advancing until liberating the whole of Marib province," he said.

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