STEAD, Nev. (AP) - Thousands of spectators joined officials at the National Championship Air Races to pay tribute to emergency personnel who saved countless lives after last year's mass casualty crash at Reno-Stead Airport.

Reno Air Race President Mike Houghton said Thursday's formal opening ceremony was a somber memorial to those killed in an "unthinkable tragedy" and "a humble tribute to the compassion on display under challenging circumstances."

The pilot and 10 people on the ground were killed last Sept. 16. More than 70 were injured.

Among those recognized Thursday were four Reno nurses who raced from a first aid station behind the grandstand to treat 20 critically injured fans. Also honored was a military crew that used a Huey helicopter that was on display that day to ferry victims to the hospital.

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