Houthi shelling kills seven civilians in Saudi Arabia

The kingdom's Ekhbariyah television channel said that the projectiles landed in an industrial area in the city of Najran, close to the Yemeni border.

According to Reuters, local residents reported a state of panic after the shells landed some 500 metres from a power plant.

A spokesman for the country's Civil Defense Directorate said four Saudi nationals and three expatriate residents had been killed in the shelling. 

The attack is one of the deadliest that Saudi Arabia has seen since it entered Yemen's conflict in March 2015 to back Yemen's President Abedrabbo Mansour Hadi against the country's Houthi rebels.

During the course of the war, Houthi rebels have fired missiles into Saudi territory from their strongholds in northern Yemen, however the projectiles have often been intercepted before hitting their targets.

Numerous civilian casualties in Yemen's war have raised alarms around the world about the protection of those caught in the fighting, with both sides being accused of human rights violations.

In recent months, the Saudi-led coalition has come under heated criticism from the United Nations and international human rights watchdogs for its aerial bombardment of Yemen, which the UN says has claimed the lives over 500 children in 2015 alone.

Since UN-led peace talks between Houthis and Yemen's government broke down last week, the coalition has intensified its airstrike campaign.

In recent weeks, civilian casualties have continued to mount, with the UN recording 272 deaths and 543 injuries in the four months between April and August 2016.

More than 2.8 million people have fled their homes because of daily bombardments and shelling since the beginning of the conflict.