The preliminary results of Azerbaijan’s investigation into the deadly crash of a civilian airliner point to the plane being hit by a Russian antiaircraft missile, or shrapnel from it, said people briefed on the probe.

After an Azerbaijan Airlines jet crashed in Kazakhstan, speculation mounted about why the plane went down and whether possible Russian air defense action may have played a role.

Thirty-eight of 67 onboard flight from Baku to the Chechen city Grozny believed to have been killed. Russian authorities cite bird strike.