Investing.com -- Ryanair Holdings PLC Chief Executive Officer Michael O'Leary said today that early findings from an investigation into an incident involving a broken window on a Boeing Co 737 aircraft point to engine damage caused by a foreign object.

"Initial indication would suggest it looks like a foreign object damage to the engine on takeoff at Thessaloniki, but we don't have, we can't say that definitively," O'Leary told analysts while presenting Ryanair's results for the April-June quarter.

A passenger was partly sucked out of the aircraft's broken window during the incident.

O'Leary said a draft report on the incident is expected to be issued in about 28 days, with a more detailed report to follow.