SANAA, Yemen (AP) — Yemeni security officials say an airstrike by the Saudi-led coalition has killed at least 11 civilians.

The civilians were apparently trying to escape fighting in western Yemen on Tuesday when their vehicle was struck. The officials say the wounded include women and children in critical condition, with the death toll expected to rise.

Separately, United Nations officials say the coalition barred a U.N. flight to Yemen's capital, Sanaa, which is controlled by Shiite rebels known as Houthis. The plane was going to bring aid workers and BBC reporters from Djibouti.

The coalition has been waging an air war against the Houthis since March 2015, and shut down Sanaa's international airport a year ago.

All officials spoke on condition of anonymity because they weren't authorized to speak to the press.