A Pakistani army plane crashed into houses during a training flight, killing at least 18 people.
The aircraft hit a residential area and exploded, collapsing several homes in the garrison city of Rawalpindi near Islamabad.
All five soldiers on board were killed and 13 civilians on the ground died in the blaze early on Tuesday morning. Rescue officials said several children were among the dead and the toll could rise because some survivors were badly burnt.
The military's information wing said the aircraft was on a routine training mission when the crash occurred at about 2 am. There was no word on what type of aircraft crashed, or what the likely cause was. The downed aircraft was a turbo, twin engine, army aviation plane.
"I woke to the sound of a huge explosion. I stepped out of my house and saw huge flames and we rushed to the site," witness Mohammad Sadiq told AFP.
"People were screaming. We tried to help them but the flames were too high and the fire too intense," he said.
Several of the dead were from one family. "My sister, her husband and their three children were killed when the plane crashed into their home," said Mohammad Mustafa.
Imran Khan, Pakistan's prime minister, offered his condolences and wished a "quick recovery for the injured".
The crew were named as pilots Lt Col Saqib and Lt Col Waseem, and passengers Naib Subedar Afzal, Havaldar Ibne Ameen and Havaldar Rehmat.
One witness said the plane appeared to have been on fire immediately before the crash and was flying low.
Rescue crews and military personnel quickly arrived at the scene.
The area was cordoned off as emergency workers combed through the smoking debris.
"The plane hit the side of the building and the structure it has crashed into has completely collapsed,” an army officer at the scene told Reuters.
Safety concerns about both Pakistan's civil and military planes have been raised after previous crashes. More than a dozen military planes crashed during an 18-month period at the start of the decade, with former officers blaming an ageing fleet.
Three years ago, a plane with the national airline, Pakistan International Airlines, burst into flames after one of its two turboprop engines failed while travelling from remote northern Pakistan to Islamabad. More than 40 people died.
Pakistan's deadliest air crash was in 2010, when an Airbus 321 operated by private airline Airblue and flying from Karachi crashed into the hills outside Islamabad during bad weather. All 152 people on board died.
Pakistan's military has been on high alert since February when it clashed with neighbouring India after Delhi launched air strikes into Pakistan's territory in retaliation for a suicide bombing in Indian-administered Kashmir.