A plane failed to clear a mountain pass Monday in southeast Alaska, killing one person and injuring nine others, while another aircraft crashed into water in the same area, killing all four occupants, officials said.

Two Wrangell Air planes left Sitka 10 minutes apart bound for Petersburg Monday afternoon and when the second plane arrived first, officials knew something was wrong.About the same time, a high-flying jet reported picking up an emergency signal in the mountains, and helicopters were sent to the scene.

Arnold Johnson of Mountain Aviation in Sitka got there first and found a badly wrecked twin-engine Burton Islander with four passengers standing by the plane waving for help.

In the other accident, a private Cessna 172 left Petersburg for Wrangell late Sunday and never arrived, triggering an all-night search that ended at dawn Monday when the Coast Guard cutter Cape Hatteras found the upside-down plane submerged in 12 feet of water.