In this Sept 14, 2020 photo, a fighter loyal to Yemen's Houthi rebels stands guard during a rally commemorating the death of Shiite Imam Zaid bin Ali in the capital Sanaa. (MOHAMMED HUWAIS / AFP)

SANAA - The Saudi-led airstrikes targeted and destroyed the reinforcements of the Houthi rebels in Yemen's central province of Marib as the rebels intensified their ground offensive against the Yemeni government forces in the past 24 hours, a military source said Tuesday.

"Several vehicles of the rebels in Sirwah district and adjacent areas were hit and destroyed, killing all on board," the source in Marib told Xinhua on condition of anonymity.

Houthi-run al-Masirah TV reported that the Saudi-led coalition launched 18 airstrikes on the districts of Sirwah, Raghawan, Jabal Murad and Majzar in the western and southern parts of Marib

The heavy clashes and exchange of artillery shelling continued as the Yemeni government forces pushed back Houthis' further ground attacks, he said.

Meanwhile, Houthi-run al-Masirah TV reported that the Saudi-led coalition launched 18 airstrikes on the districts of Sirwah, Raghawan, Jabal Murad and Majzar in the western and southern parts of Marib.

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The Houthis began in February a major offensive on Marib in a desperate attempt to seize control of the oil-rich province, the government's last northern stronghold.

The United Nations has warned that the offensive on Marib, which hosts nearly 1 million internally displaced people, could lead to a major humanitarian catastrophe.

Yemen's civil war flared up in late 2014 when the Houthi group seized control of much of the country's north and forced the internationally recognized government of President Abd-Rabbu Mansour Hadi out of the capital Sanaa.

The Saudi-led Arab coalition intervened in the Yemeni conflict in March 2015 to support Hadi's government.

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