MARIB, Yemen: Fighters loyal to Yemen's Saudi-backed government walk at a position near the frontline against the Houthi rebels in Yemen's northeastern province of Marib Monday. - AFP

RIYADH: Saudi forces yesterday destroyed an explosive-laden boat off the coast of the Red Sea port of Yanbu, the defense ministry said. "A bomb-laden unmanned (vessel) was intercepted and destroyed this morning," the ministry said in a statement, published by the official Saudi Press Agency. "Naval units were able to detect and monitor the activity of the bomb-laden (boat) in the Red Sea waters off the shores of Yanbu." No group has so far claimed responsibility for the incident, which the ministry said was under investigation.

The incident comes as fighting escalates in neighboring Yemen between Saudi-backed government forces and Houthi rebels. Yanbu, 860 kilometers (535 miles) east of the Saudi capital Riyadh, lies some 975 kilometers north of Saudi's frontier with Yemen. Houthi insurgents are ramping up a bloody offensive to seize the oil-rich Marib region, the Yemeni government's last stronghold in northern Yemen.

The Houthis, who are battling the Saudi-led military coalition that intervened in Yemen's war in 2015, have also stepped up drone and missile strikes on Saudi targets, including its oil facilities. The rebels have used bomb-rigged boats in the past to target the kingdom. Last week, Greece said it will transfer a Patriot missile battery to Saudi Arabia to protect its critical energy infrastructure, as the Gulf kingdom grapples with the growing attacks. Maritime security firm Dryad Global said it had received reports that a ship had been "attacked" off Yanbu. But the firm later said the ship was "not involved in the incident" and it will continue to investigate.

Meanwhile, Yemen government forces have thwarted a "massive" Houthi attack west of Marib city and reinforced their positions as they defend their last northern stronghold, two military commanders and an official said yesterday. But they said the Iran-backed insurgents had advanced in four areas of the Mashjah front, another key battlefield in their battle to seize the oil-rich region from Saudi-led coalition-backed government forces. Fierce fighting on multiple frontlines around the strategic city has left at least 67 dead over the past 24 hours, including some 27 loyalist personnel, the three sources said.

According to one of the commanders taking part in the defense of Marib, the government forces "succeeded in repelling a massive attack" at Al-Tala'a Al-Hamra, about 18 kilometers (11 miles) west of the city. "Losing it would enable (the rebels) to advance towards hills and sites close to Marib, and the road would be clear towards the western entrance to the city," the source added.

The second commander confirmed the details. Al-Tala'a Al-Hamra is located near the main highway connecting Marib with the rebel-controlled capital Sanaa. On Sunday, military sources told AFP that the rebels had taken full control of the Kassara battlefield to the northwest, putting them within six kilometers (four miles) of the city center, as well as progressing on western frontlines despite Saudi-led coalition airstrikes. - AFP