Saudi forces have been carrying out air and artillery strikes on Yemen
Saudi Arabia says it has captured a strategic mountain area near its border with Yemen from Yemeni Shia rebels.
Saudi forces detained about 150 Ethiopians and Somalis as prisoners of war as they cleared the area, Saudi Arabia's deputy defence minister said.
The Houthi rebels denied that the area, which is known as Jabal al-Dood or Jabal Mudood, had been taken.
They also said they had no connection with the Somalis and Ethiopians who had been taken prisoner.
Saudi forces have been carrying out air and artillery strikes on Yemen for several weeks, after the rebels killed a border guard in a raid.
"The armed forces completely control al-Dood mountain, one of the most strategic regions," deputy defence minister Prince Khaled bin Sultan was quoted as saying as he inspected troops just within Saudi territory.
He also said Saudi forces had "cleaned up every inch of Saudi territory," adding that "any person who infiltrates or sniping will end up either surrendering or dead".
The rebels said Saudi Arabia had carried out further air attacks - but they said there had been no clashes on the ground, and that Saudi troops were not in control of the area.
They said it was the Saudis who relied on foreigners to protect themselves.
The Saudi minister's comments come days after rebels said this week that they had captured nine Saudi soldiers.
They have also published video clips suggesting that they have seized large quantities of weapons from Saudi troops.
All this leaves Saudi Arabia facing questions about the effectiveness of its expensively-armed forces, says BBC Arab affairs analyst Bob Trevelyan.
The rebels, seeking autonomy in northern Yemen, appear to be well-motivated and have the advantage of better local knowledge of the difficult terrain, he says.
The rebels accuse Riyadh of supporting the Yemeni armed forces by letting them launch attacks from its territory.
The Houthi rebels, named after the family of their leader, say they are trying to reverse the political, economic and religious marginalisation of the Zaydi Shia community.
The Zaydi community are a minority in Yemen, but make up the majority in the north of the country.
The insurgents have been fighting the government since 2004.
The government launched a fresh offensive in August 2009, which precipitated a new wave of intense fighting.
It accuses the Houthis of wanting to re-establish Zaydi clerical rule, which ended in 1962.
Aid agencies say tens of thousands of people have been displaced.