A laser pen was shone into the cockpit of a plane flying at 29,000ft (8,840m), police have said.
The Scandinavian commercial flight from Manchester to Billund, Denmark, was targeted at about 18:45 GMT on Sunday, said Humberside Police.
The captain reported to National Air Traffic Services (NATS) that the cockpit was lit up as the plane flew over North East Lincolnshire.
Using flight data NATS assessed the laser came from the Grimsby area.
No ill-effects were reported by the crew other than being dazzled and there was no other impact on the flight, said the force.
People targeting transport with laser devices could be jailed for up to five years under the Laser Misuse (Vehicles) Act, it added.
Police are appealing for anyone with information to contact them.