A laser was shone at a commercial aircraft in the Londonderry area, police have said.
The Fly BMI flight was inbound to the City of Derry Airport from London Stansted.
PSNI sergeant Nick Rainey said: "This could have had terrible consequences, and I would ask anyone with information that could assist in our investigation to contact us."
The incident was reported at 9.45pm last Thursday.
Sgt Rainey said he believed the laser was shone from somewhere between the Magheramason and Newbuildings area.