A Saudi-led military coalition fighting the Houthis in Yemen said it downed a drone on Sunday that the Iran-aligned group has said they launched in the direction of a Saudi airbase.

“The coalition forces intercepted and downed a drone launched from the city of Sanaa in the direction of Khamis Muchait’s residential neighborhoods,” coalition spokesman Colonel Turki al-Malki told the official Saudi Press Agency.

A Houthi military spokesman cited by the group’s Al-Masirah TV earlier said the group had launched drones targeting the control towers of the Abha airport and the Khamis Mushait airbase, both in the southwest of the kingdom.

The Houthis, who control Sanaa, the Yemeni capital, have stepped up their attacks against targets in Saudi Arabia in the past few months.

In response, the Saudi-led coalition fighting the Houthis has targeted military sites belonging to the group, especially around Sanaa.

The escalation in violence threatens a U.N.-sponsored deal for a ceasefire and troop withdrawal from the coastal city of Hodeidah, which became the focus of the war last year when the coalition tried to seize its port.

The port is the Houthis’ main supply line and a lifeline for millions of Yemenis.Reuters