A passenger plane has been forced to make an emergency landing at Leeds Bradford Airport after smoke from one of its engines filled the cabin.
All 56 passengers and four crew on the Birmingham to Edinburgh flight were led to safety after the aircraft landed.
Mike Rutter, from low-cost airline Flybe, said the aircraft was diverted as a precaution because of the thickness of the smoke.
He said an investigation was under way and normal services had resumed.
Mr Rutter said: "This was caused by smoke, not fire, from an engine.
"We landed within 12 minutes of the captain becoming aware of the problem.
"As a precaution, everybody was braced for an emergency landing and all passengers were evacuated."
No-one was injured during the landing, although one elderly lady has since suffered a "stress-related incident", Mr Rutter added.
The plane has been taken out of service for examination.
Passenger Brian Goldthorpe told BBC Radio Leeds that he had been left in "deep shock" by the incident.
He said: "We heard a smoke detector go off and then there was a slight haze in the cabin.
"The smoke got more and more dense and the next thing the cabin crew appeared in smoke hoods and advised us there was a major incident and that the pilot was going to attempt an emergency landing.
"I could not believe it really. You are just hoping they can get the plane down before there's complete catastrophe."
Normal services have resumed at Leeds Bradford Airport
Student Leyla Turkoglu, 19, from Birmingham, said the drama began 20 minutes into the flight.
She said: "Some passengers thought someone was smoking in a toilet and there was a lot of tutting.
"The air stewardess went to the toilet to find out what was happening. She opened the door and when she turned round her face was ashen.
"Smoke started coming out, it wasn't thick black smoke, it was pale grey and it started coming into the cabin.
"The crew were wearing smoke hoods and people began shouting `where's mine?'
"It was horrible. I thought to myself this is a horrible way to die.
"It was a strange atmosphere in the cabin. The girl in front of me was sobbing, not hysterically but she was obviously upset. The old lady sitting next to me held my hand and you could see some people shaking.
"Others behind me were just joking and saying: 'Oh well'."