Yemen’s Iran-aligned Houthi movement said it launched a drone attack on a Patriot missile battery in the airport of the Saudi city of Najran near the Yemeni border, the group’s Al-Masirah TV said on Thursday.

Axar.az reports citing foreign media that the Houthis, who ousted the Saudi-backed Yemeni president from power in the capital Sanaa in 2014, have stepped up missile and drone attacks on Saudi in the past ten days in a resurgence of tactics that had largely subsided since late last year amid United Nations-led peace efforts.

The group claimed responsibility for last week’s armed drone strikes on oil assets in Saudi Arabia and on Sunday said they would attack 300 vital military targets in Saudi Arabia, the United Arab Emirates, and Yemen.

This is the third Houthi strike or attempts to strike Najran in a week, according to Saudi and Houthi reports.

The latest hostilities coincide with rising tensions between Iran and Gulf Arab states allied to the United States and come just as a sensitive, U.N.-sponsored peace deal is being carried out in Yemen’s main port of Hodeidah, a lifeline for millions.

There was no Saudi confirmation of Thursday’s attack. Al Masirah did not say what damage resulted from the attack.