Four Saudi soldiers reportedly died and eight others wounded after shelling from the Yemeni border, in Dhahran al Janoub, along the Aseer region of the kingdom, on Friday.
Saudi government sources have not given information yet on who carried out the shelling, but suspicions were drawn towards the Iranian-backed Houthi rebels who are rivals with Saudi forces and carried out similar attacks in the past.
A Houthi-run news agency also said on Friday that they were launching rockets on various Saudi areas.
Missile launchers were destroyed by Saudi forces after the shelling took place.
A Saudi-led coalition has targeted the Houthi rebels in Yemen since late March, after the rebels forced the country’s President Abd Rabbuh Mansur Hadi to exile.
Hadi fled to Riyadh in March this year as the Houthi forces seized the capital, Sanaa, in September, 2014, and forcibly closed the Yemeni parliament earlier this year.
Four months of air raids and constant clashes have killed more than 3,500 people in Yemen as the port city of Aden suffered the most due to shortages of food, medicine and fuel.
The UN has declared the situation in Yemen to be a level-three humanitarian emergency, the highest on its scale, after about 80 percent of the country’s population fell into dire need of humanitarian aid.
Twenty million people in the country are in need of aid, 13 million are facing food shortages and 9.4 million are having difficulties accessing drinking water.