Five people were hospitalized on Sunday after an unexpected turbulence episode on an American Airlines flight between Miami and Raleigh-Durham.

Flight 1286, operated by an Airbus A321, experienced turbulence while the seatbelt sign was on, the airline said.

The plane landed safely at Raleigh-Durham International Airport around 10:50 p.m., when the crew reported possible injuries to passengers and flight attendants, the Federal Aviation Administration said.

American Airlines said three crew members and two passengers were taken to a local hospital for observation. All were released Monday.

“We thank our crewmembers for their professionalism and our customers for their understanding,” the company said in a statement.

The FAA has launched an investigation into the incident.