Two Saudi border guards were killed and five wounded by shells fired from Yemeni forces, Saudi Interior Ministry spokesman said late on Wednesday.
Saudi state news agency SPA said the border guards were killed at a military post in Dhahran al-Janoub, along the border with Yemen, when projectiles fired from the Yemeni side.
Independent sources confirmed that the Yemeni forces have launched successful attacks on several military bases in Saudi Arabia.
Two Saudi tanks together with a military personnel were destroyed in Al-Shobheh base in Dhahran al-Junob in Saudi Arabia, the sources said.
The second region was Takhieh that was attacked by Yemeni rockets, where a Saudi armored vehicle was destroyed and its military personnel were all killed, they added.
In the Northwest, the Yemen army and popular forces fired rockets and mortar shells at Al-Radif military zone, and destroyed Saudi military positions.
Saudi Arabia has been bombing Yemen in the last 64 days to bring its ally, fugitive president Mansour Hadi, back to power.
The airstrikes have so far claimed the lives of more than 4,113 civilians, mostly women and children.
According to a recent report by Freedom House Foundation, most of the victims of the deadly Al Saud campaign are civilians, including a large number of women and children.
Thousands of residential buildings have been destroyed, and hundreds of civil and public facilities were reduced to rubble as a result of the bombardments by Saudi warplanes on the Yemeni cities and towns, the group said.