SINGAPORE — Singapore Airlines said Monday there were no injuries when a jetliner caught fire after returning to Changi Airport because of an engine warning.

The Boeing 777-300ER was on its way to Milan when it turned back ‘‘following an engine oil warning message,’’ the company said. The cause of the fire has not been determined.

The airline said the aircraft’s right engine caught fire after Flight SQ368 touched down more than four hours after taking off.

‘‘The fire was put out by airport emergency services and there were no injuries to the 222 passengers and 19 crew on board,’’ Singapore Airlines said in a statement. The jet was sprayed with foam to keep the fire from spreading.

Passengers watched from inside the plane as emergency crews extinguished the blaze along the right wing. They were asked to remain seated and keep calm, witnesses said.

The passengers who wished to continue their journey were transferred to another aircraft bound for Milan, the airline said.

Aviation analysts said fuel often clings to the surface of planes as they slow down to land, and sparks from hot brakes might have ignited the fire.

The country’s transportation ministry said the investigation would also seek to determine whether procedures can be improved.

Associated Press