Doctors Without Borders says its staffers are "scared" to resume their work in a facility it supports in the northern Yemeni city of Saada after two nearby airstrikes by the Saudi-led military coalition.

The aid group says in Twitter postings that the airstrikes hit 20 meters from the hospital on Tuesday and bombings have forced evacuation of their facility in the Razeh district in Saada. The city is the stronghold of Shiite Houthi rebels and the Saudi coalition has declared it a military zone. The same facility came under airstrikes in January where four were killed and 10 injured.

Houthis captured the Yemeni capital Sanaa in September 2014 and in March 2015, the Saudi-led coalition started an extensive air campaign in support of the internationally-recognized government.