Yemen’s civil war spilled into neighbouring Saudi Arabia for the first time yesterday when Shia gunmen shot dead a Saudi security officer in a cross-border attack.

The Shia rebels, known as Huthis, have been backed up against the Saudi border by a Yemeni army offensive launched this summer.

The rebels accuse the Saudis of allowing Yemeni troops to attack them from behind, using a military base in the Saudi town of Jebel al-Dukan.

The kingdom’s news agency said that rebels had entered Saudi territory and attacked patrols.

“The infiltrators used various weapons to fire at the border guard patrols, causing the martyrdom of one security officer and wounding 11 others,” it said. Some Shia rebel sources claimed to have taken complete control of the town after defeating Saudi forces there.

They accuse Saudi Arabia, a conservative Sunni Muslim country, of backing the Yemeni army, fearing the emergence of a strong Shia militia similar to Hezbollah in Lebanon.

In turn, the Yemeni Government in Sanaa has accused Iran, a Shia theocracy, of supporting the Huthi rebels as part of a campaign to spread Tehran’s influence across the region. The Government said last week that Yemeni troops had seized five Iranians on a boat loaded with arms in the Red Sea.

Yemen has denied receiving any support from Riyadh, but the tensions emphasised the increasingly fragile situation on the borders of the world’s biggest oil exporter. There are increasing signs that al-Qaeda — whose founder, Osama bin Laden, is of Yemeni origin — is using the strife in the country as a means of establishing a dangerous presence close to Saudi Arabia, where it has launched deadly attacks in the past.

Sanaa stepped up its efforts to crush the Shia rebels in August when it launched a land and air offensive that aid groups say has driven 150,000 people from their homes, as well as killing and wounding hundreds.

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