Saudi Arabia says Yemen's Shia rebels have launched two separate attacks along the kingdom's border, killing three Saudi soldiers.

The Wednesday night attacks reflect how despite three months of Saudi-led airstrikes targeting the rebels known as Houthis, the rebels are still capable of launching deadly attacks along the kingdom's border.

The Saudi Press Agency carried a military statement on Thursday, saying that two soldiers died in the border region of Najran, while the third died in the region of Asir.

Houthis frequently fire missiles from inside Yemen at Saudi border posts. More than two dozen Saudi soldiers have been killed in such attacks.

The unrest in Yemen has killed more than 1,000 civilians since March, displaced more than a million and led to severe shortages of food, water and electricity.