Two skydivers were killed in California when their parachute apparently failed to open during a tandem jump at a skydiving centre near Lodi.
US authorities said the two men were found dead in a vineyard in Acampo.
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Sheriff's Deputy Les Garcia told the Associated Press that it appeared the parachute did not deploy until after impact.
Witnesses said they did not see a parachute open.
Bill Dause, owner of the Parachute Center, told NBC News that the instructor involved was highly experienced.
"The parachute failed to eject properly," he said. "We have no explanation why. The only thing it looks like is something may have gone out of sequence. That may have caused the problem".
The incident is being investigated by the Federal Aviation Administration.