The Saudi-led coalition in Yemen said Sunday it had intercepted and destroyed eight explosive-laden drones fired by Houthi rebels towards Saudi Arabia.

In a statement, coalition spokesman Col. Turki al-Maliki accused the Houthi rebels of “deliberately and systematically targeting civilians and civilian areas in the kingdom”, according to the Saudi SPA News Agency.

He said the Saudi-led coalition “is enforcing procedures to protect civilians and civilian areas in accordance with international humanitarian law”.

There was no comment from the Houthi group on the statement.

Despite calls by the US administration for the Houthi group to suspend military operations and return to negotiations, the rebels have intensified their drone attacks on Saudi Arabia.

On Tuesday, the US administration imposed sanctions on two Houthi leaders for what it said their responsibility for exacerbating the conflict in Yemen.

The Yemeni group, backed by Iran, regularly announces rocket and drone attacks on Saudi territories, saying they are a reaction to the Saudi-led coalition’s assault on Yemen.

Yemen has been wracked by violence and instability since 2014, when Houthi rebels captured much of the country, including the capital Sanaa.

A Saudi-led coalition aimed at reinstating the Yemeni government has worsened the situation, causing one of the world’s worst man-made humanitarian crises with nearly 80% or about 30 million of its people needing humanitarian assistance and protection and more than 13 million in danger of starving to death.