A plane split wide open after crashing and bursting into flames – killing at least three.
The incident injured more than 100 people after the Boeing 737-800 skidded off the runway at Sabiha Gokcen airport in Istanbul, according to Turkish officials.
Later it emerged three people had died, according to Turkish news outlet Biz10 TV.
It landed in wet weather, and was carrying 177 passengers and six crew members.
The condition of those injured is not known at this stage.
Shocking footage shows passengers evacuating the Pegasus Airlines plane through cracks in the fuselage.
A spokeswoman for Pegasus Airlines confirmed the crash but did not provide further details.
Istanbul Governor Ali Yerlikaya said on Twitter that emergency response teams were working to evacuate the passengers.
Footage on Turkish media showed the plane's fuselage, as well as a section of it near the tail, had broken off.
Passengers were being led out as the plane lay on a patch of grass next to the runway.
Earlier footage showed part of the exterior of the plane had caught on fire.
The airport has been closed, and it is not known when it will re-open.
It was on a domestic flight within Turkey.
According to reports flights will be diverted to another airport in the city.
Live television footage showed dozens of rescue crew members working around the flood-lit fuselage, including the cockpit which had flipped over.
The Transportation Ministry said it was a "rough landing".
The accident comes a month after another Pegasus plane skidded off the runway in Istanbul at the same airport.
There were no deaths or injuries in that incident on January 7.
It is rare for a fuselage to split open while pieces remain largely intact.
Planes are designed to absorb impact forces in the bottom of the fuselage to improve the chances that passengers in the cabin above will survive.
In 2013, the tail of an Asiana Airlines Boeing 777 broke off after the jet hit a seawall during approach to San Francisco International Airport.
Three people died, 49 were seriously injured and scores more suffered minor injuries, according to the US accident report.
Istanbul governor Ali Yerlikaya said the plane landed in bad weather, failed to "hold on to the runway" and skidded some 50 or 60 metres before crashing into a ditch from a height of some 30 metres.