After the Kentucky-bound Flight 485 had taken off from Florida’s Fort Lauderdale-Hollywood International Airport, the pilot “received an automated alert about another aircraft at the same altitude,” the FAA said.

An air traffic controller in the Miami Air Route Traffic Control Center had instructed the plane “to turn eastbound at an altitude of 23,000 feet when it crossed in front of a northbound Gulfstream business jet,” the FAA said.

The pilot of the Gulfstream jet also took evasive action after receiving a similar alert, the FAA said.

The Allegiant plane returned to the Fort Lauderdale airport, where the injured flight attendant was treated for injuries, said the FAA, which added it is investigating the incident.

Allegiant declined to comment on the incident.

‘We went straight up,’ passenger said

One of the Allegiant passengers, Jerrica Thacker, 21, told CNN the plane suddenly “went straight up” in the air.

“It truly felt like a roller coaster,” Thacker, who was trying to flying home with family to Kentucky, said. “We went up and down and then leveled out.”

“It felt like we were nose diving, but we later found out that we went straight up. … I was terrified.”

Two flight attendants fell backwards when the plane ascended, one of whom stayed on the ground for five minutes before she was helped up and escorted to the rear of the plane, Thacker said.

“The flight crew asked if there were any medically trained individuals on the plane,” she added.

About 20 minutes after the maneuver, the pilot told passengers over the intercom that the plane was returning to Fort Lauderdale and that he had to make the abrupt maneuver to avoid a collision, Thacker said.

After the pilot relayed the message, Thacker saw people praying and crying, she said.

“I was looking forward and trying my best to breathe to avoid a panic attack,” she said.

Instead of getting back on a plane, Thacker and her family rented a car and drove 15 hours to Kentucky, she said.

“We were all too shook up to fly again,” she said.