(NBC News) Two acrobats are in critical condition following a horrific accident during a Sunday performance in Providence, Rhode Island.
Investigators say a broken clamp appears to be to blame for the rigging collapse that sent eight acrobats, suspended by their hair, plummeting to the floor below, where they landed on a ninth person below.
The stunt had been performed publicly, without incident, about 150 times prior to Sunday.
The nine performers suffered serious injuries, mostly broken bones, though none are believed to be life-threatening.
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