A plane carrying up to 127 people has crashed in a residential area near Islamabad international airport.
Aviation officials said the Bhoja Air jet, flight BHO-213, was flying from Karachi to Islamabad when it crashed in bad weather near Chaklala, Rawalpindi.
Emergency teams are at the crash site, reported to be at Hussain Abad village near Bahria town.
There are no reports of survivors. Rescue teams are trying to assess if there are any casualties on the ground.
Reports suggest the plane, believed to be a Boeing 737 carrying 118 passengers and nine crew, was making its final approach to the airport when the crash happened.
Hafeez Chachar, of the BBC Urdu service, who is near the site of the crash, said seats from the plane were strewn around and that people were searching the wreckage using light from their mobile phones.
Witness Samab Ahmad told BBC World: "I'm working on a construction site not far from the landing strip and I saw it with my own eyes. I saw the plane crash land and then suddenly catch fire.
"It crashed on top of some sort of building, which could be residential. I can still see the fire from the distance. It's a terrible, terrible scene. I heard the emergency services going to the scene too, including a helicopter."
Saifur Rehman, from a police rescue team, told Geo TV: "Fire erupted after the crash. The wreckage is on fire, the plane is completely destroyed.
A police official at the crash site, Fazle Akbar, told AFP news agency the plane had been totally destroyed and it would be a miracle if there were any survivors.
The jet left Karachi at around 17:00 local time (12:00 GMT) and had been due to arrive at 18:50 (13:50 GMT).
There were reports of rainstorms in the area at the time, but it is likely to take investigators weeks to determine the cause of the crash.
Bhoja Air is a small new commercial airline which was started about 10 years ago but closed because of financial difficulties. It recently re-opened.
Last July, an Airbus A321 crashed as it was about to land in Islamabad, killing all 152 people on board.
Although Pakistan's air industry has been booming, critics say standards have not always kept pace with the increase in services.