Saudi troops are enforcing a buffer zone in north Yemen
Shia rebels in northern Yemen say Saudi Arabia has carried out more bombing raids, targeting several villages along the border.
The rebels say Saudi planes also struck a mountainous area more than 10km inside Yemeni territory.
There's been no word on any casualties from the recent raids.
Earlier this week, the Saudi authorities said they would keep bombing northern Yemen until the rebels had pulled back from the border.
The rebels, known as the Houthis, say their grievance is with the Yemeni government, and that Saudi Arabia should stay out of the conflict.
Saudi Arabia has evacuated 240 villages because of the fighting according to a statement by UN children's fund, Unicef.
The UN body also said more than 50 schools had been closed because of the fighting and that there was a "deep concern about the escalation of the conflict".
A Saudi government official said on Thursday that Saudi forces were using air power and artillery to enforce a 10km-deep buffer zone inside northern Yemen to keep the rebels away from the border.
An estimated 150,000 people have been displaced by the conflict since 2004
Riyadh had previously claimed troops were only attacking the rebels inside Saudi territory.
The Houthi rebels are drawn from the Zaidi Shia community, who are a minority in Yemen but make up the majority in the north of the country.
They first took up arms against the government in 2004, saying they wanted greater autonomy and a greater role for their version of Shia Islam. They complain that their community is discriminated against.
The Yemeni government launched a fresh offensive against the Houthis in August 2009, which has precipitated a new wave of intense fighting.