A charter plane has crashed shortly after take-off from Karachi airport and reports say all 21 people on board have been killed.
Pervez George, a spokesman for the country's Civil Aviation Authority, told Geo TV there had been a "problem in one of the engines".
Rescue leader Lt Col Noor Alam said there were no survivors.
The aircraft is thought to have been carrying oil company employees to an oil field in Sindh province.
"The plane has been destroyed," Lt Col Alam, was quoted by Reuters news agency as saying.
"The dead bodies are burned beyond recognition. It could not be recognised whether they are men or women. We don't know nationalities."
The incident comes four months after an airliner crashed in stormy weather into the hills around the Pakistani capital Islamabad, killing 152 people.
Karachi is the capital of Sindh province. The city, with a population of about 18 million, is Pakistan's largest and the nation's financial centre.