The Houthi rebels, locked in a war against Yemen's Saudi-backed government, said they had fired a missile at the kingdom's southwestern province of Najran in a statement tweeted by their Al-Masirah television channel.

Qatar Armed Forces' troops in Najran arrived in Doha after participating in military operations as part of the Arab coalition forces.

A Saudi power relay station was set on fire on Friday by a projectile fired from neighbouring Yemen towards the southern Saudi Arabia, Saudi state news agency SPA reported.

Rockets fired by Yemeni rebels into a Saudi border city on Saturday killed a Saudi civilian and wounded six others including a Pakistani man, the Saudi civil defence agency said.