Swiss International said that a flight from Delhi to Zurich had to abort its takeoff early on Sunday after an engine issue, adding that four passengers and one crew member were injured.

The airline did not elaborate, but the Economic Times reported that one of the engines had caught on fire as the plane was accelerating down a runway and that the passengers were injured during an emergency evacuation.

“Shortly after 1am local time on April 26, an issue occurred with one of the engines during the takeoff of flight LX147 in Delhi. The crew aborted the takeoff and, after assessing the situation, decided as a precaution to evacuate the aircraft,” Swiss International said in a statement.

It said that it had set up a task force to look into the incident, adding that the injured passengers were taken to a hospital, while the crew member had sustained a sprained ankle.

The airline had earlier said that six passengers had been injured but revised the number.

There were 228 passengers, four infants and 13 crew members on board the aircraft, which was an Airbus A330.

Delhi’s Indira Gandhi International Airport declared an emergency following the incident, but runway operations have since resumed, said a source familiar with the matter who was not authorised to speak on the issue and declined to be identified.

In its statement, the airport said its operations remained unaffected.