RIYADH (Reuters) - Yemen's Shi'ite rebels said they had captured some Saudi soldiers on Friday, after Riyadh said it would press on with its offensive until it had cleared them from its territory.
A Saudi official said on Thursday that Riyadh had launched air strikes on rebels in northern Yemen after the Shi'ite insurgents made a cross-border raid earlier in the week.
But the Saudi Press Agency (SPA) said on Friday the strikes were "focussed on infiltrators in Jabal Dukhan and other targets within the range of operations within Saudi territory."
Rebel Yemeni spokesman Mohammed Abdel-Salam told Al Jazeera television by telephone "We will carry out interviews with them (for the media) ... they will be treated with respect," and reiterated his group's position that Saudi forces had crossed the border into Yemen.
Saudi officials were not immediately available for comment. Abdel-Salam did not say how many soldiers were in rebel hands.
Saudi Arabia, the world's top oil exporter, has become increasingly anxious about instability in Yemen, which is facing a Shi'ite insurgency in the north, separatist sentiment in the south and a growing threat from resurgent al Qaeda fighters.
"The entry of the gunmen to Saudi territory, the aggression against border patrols...and presence on Saudi soil is a violation of sovereignty that gives the kingdom every right to take all measures to end this illegitimate presence," SPA reported, citing an official source.
"The operations will continue until all sites within Saudi territory are cleansed of any hostile element."
Riyadh will take unspecified measures to prevent any future incursion by the Yemeni rebels, the source said, adding that armed forces units had been deployed to back border guards.
The rebels accused Saudi Arabia of attacking villages inside Yemen.
"Saudi aircraft are bombing the Malaheet province and the surrounding Yemeni border villages," they said in a statement.
On Thursday, Saudi government officials said the air force had bombed Yemeni rebels who had seized a border area inside the kingdom, which they said had been recaptured. They said at least 40 rebels had been killed in the fighting.
Yemen's government -- which has long dismissed accusations by rebels that it has colluded with Riyadh to combat them -- has denied that Saudi planes had struck across the border.
At least 40 rebels surrendered during the air strike in the Jebel Dukhan region, an Al Arabiya correspondent told the Saudi-owned network from the region, citing unnamed sources.
Saudi aircraft and artillery were still pounding targets, the reporter said.
Saudi Arabia said on Wednesday a security officer was killed and 11 were wounded in an attack by gunmen who had crossed the border from Yemen -- the first such reported incursion since the long-running Houthi revolt flared up again in August.
The Shi'ite rebels, known as Houthis after the family of their leader, have previously accused Saudi Arabia of backing Yemen's armed forces in the conflict. Sanaa had denied this.
The 1,500 km (930 mile) border with Yemen is a security worry for Riyadh, which is building a high-tech border fence to prevent infiltration.
U.S.-allied Arab countries such as mainly Sunni Muslim Saudi Arabia and Egypt fear Shi'ite power Iran could gain influence in Yemen through the Houthis. The rebels deny getting any help from Tehran, which has offered to mediate in the conflict.
Yemen's army launched Operation Scorched Earth in August to crush the rebellion. Aid groups say around 150,000 people have been displaced by the fighting, which first broke out in 2004.
A United Nations refugee agency official in Geneva said on Friday the body hoped an aid convoy carrying shelter supplies from the Saudi side would be able to enter north Yemen in coming days. It was not clear if the fighting would delay the convoy.
A spokeswoman of the U.N. humanitarian agency said the condition of Yemenis displaced by war between the rebels and government forces "is becoming increasingly challenging."