A Romanian airliner ended up off the runway while landing at Rome's main airport during heavy winds on Saturday night, injuring a flight attendant and four passengers, aviation officials said.

The flight was being operated by Romanian airline Carpatair on behalf of Italian airline Alitalia.

The Italian news agency ANSA said the injuries consisted of fractures or bruises, and that none was life-threatening.

ANSA said the ATR 72 aircraft ended up in the grass about 50 metres away from the runway on a flight from the Tuscan city of Pisa, with 46 passengers and a crew of four on board.

It quoted unidentified passengers as saying the aircraft landed hard on the runway, then appeared to have bounced, ending up off the tarmac and tilted on one side.

An official statement on posted on the Alitalia website said that due to "strong wind" the aircraft flying from Pisa to Rome's Leonardo da Vinci airport "experienced difficulties in landing."

It said "all 46 passengers and the four crew members evacuated the aircraft. Passengers requiring treatment were taken to the hospital. Only one passenger had a fracture of the femur."

According to their website all Alitalia flights operated by Carpatair have been suspended.

An official from Italy's civil aviation authority ENAC said the cause of the incident was under investigation but that heavy winds that had whipped Leonardo da Vinci airport much of the day might have played a role.