Saudi Arabia says three soldiers have died and four are missing after clashes with rebels to retake land on its border with Yemen.
Reports say Shia rebels had crossed the Saudi border earlier in the week and taken an area called Jabal Dukhan.
The Saudi news agency quotes a senior official as saying 15 soldiers were wounded in the clashes.
Saudi Arabia, which says it restricted air strikes to its side of the border, says the area has been retaken.
A senior Saudi defence official said the border area had been "cleansed".
The Saudi military say the attacks are in response to an incursion into the Kingdom last Tuesday, in which a Saudi security officer was killed.
The rebels say they were attacked first and accuse Saudi Arabia of allowing the Yemeni army to use its territory to launch cross-border strikes on them - allegations denied by the Saudi authorities.
The rebels, known as Houthis, have been engaged in an intense wave of fighting with the Yemeni army since the government launched a major new offensive in August 2009.
Jabal Dukhan is a mountainous area that straddles Saudi Arabia's border with Yemen.