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.
IF ISRAEL BOMBED VILLAGES TO CREATE A BUFFER ZONE IN GAZA - OR IF NATO DID IT IN PAKISTAN'S BORDER REGION WITH AFGHANISTAN , THEN THERE'D BE HELL TO PAY.
THE SAUDI'S ARE RIGHT TO DO THIS.
ISRAEL AND NATO SHOULD DO MORE OF IT.