ISTANBUL (AP) -- Kristi Castlin has been disqualified from the 60-meter hurdles at the world indoor championships after stopping in her tracks as the rest of the pack took off toward the finish line.

The American cursed to herself as she walked off the track, and added "I don't understand."

In the Atakoy Arena, the starting pistol echoes off the walls, and it led to much confusion throughout the night. Castlin was one of two casualties, along with Jamaican rival Vonette Dixon.

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