HOOPER — Weber County sheriff's investigators have finished their probe of a powered-parachute crash that injured at least six people, some of them children, during Hooper Tomato Days celebrations Monday.

The two girls, ages 3 and 5, who were flown to the hospital Monday for their injuries, have now been released.

"The sheriff's office will not be taking any criminal action against the pilot of the craft, but the case has been referred to the Federal Aviation Administration for their consideration," Weber County Sheriff's Capt. Klint Anderson said Tuesday. "We do not know what actions, if any, the FAA will take against the pilot."

Anderson identified the pilot as Michael Higley, of Hooper. Higley's young son was a passenger in the aircraft at the time of the crash.

FAA spokesman Mike Fergus said the agency is working with investigators from the National Transportation Safety Board to determine the cause of the crash.

Higley told authorities his aircraft suddenly lost lift as he crossed over power lines on the perimeter of the festival grounds, said NTSB aviation-accident investigator Josh Cawthra. Higley added that he tried to "arrest the descent" of his aircraft, according to Cawthra, but could not keep it from hitting the ground.

Higley and his son had been scheduled to fly over the crowd of families on Monday to drop candy and gifts to festival-goers. Instead — possibly due to wind gusts — the aircraft lost altitude suddenly and crashed into the crowd, injuring at least six people, Anderson said.

"There may have been others hurt less seriously, but we know of six people, including some children, who were taken by air and ground ambulances to local and (Salt Lake City) hospitals," the captain said.

The two young girls were flown by helicopter to Primary Children's Medical Center in Salt Lake City. Four children and adults were transported from the park at 5500 South and 6100 West by ambulance to McKay-Dee Hospital and Ogden Regional Medical Center. The 3-year-old had possible head injuries, and doctors treated the 5-year-old for a broken leg.

None of the injuries are life-threatening, and Anderson said those injured are expected to recover fully. Higley and his son were treated for minor injuries at the scene.

The powered parachute Higley was piloting — also called an ultra-plane — resembles a go-cart with a large rotor fan attached to the back and a parachute on top. Cawthra said investigators are unsure whether the unregistered craft should have been registered, based on its specifications.

"We're still trying to determine what regulations the operation fell under," he said. "We're just waiting for a lot of information to come in over the next day or two."

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