The Saudi-led Arab coalition said on Saturday it had targeted armed drones in Yemen's ports of Hodeidah and al-Salif that were being prepared to be used in attacks.
The coalition gave the Iran-backed Houthi militias three hours to remove weapons from protected areas, starting with Sanaa airport, and the Salif and Hodeidah ports.
It warned that the Houthis' use of these protected areas for military purposes no longer renders them safe from attacks.
It noted that the militias had used such areas to launch attacks against oil facilities in Saudi Arabia.
The coalition said the military operation it had launched earlier on Saturday will continue until social security is achieved.
It revealed that it had destroyed four booby-trapped vessels at Salif port. The vessels were to be used in an imminent attack against oil tankers.
Three explosives experts were killed in the operation.
The coalition said the Houthis are using Sanaa's Hada neighborhood to store weapons and use civilians as human shields. It called on civilians to stay clear of Houthi weapons caches and locations.