The two officials said they were anonymous because they were not authorized to make statements to the media, the Associated Press (AP) news agency said.
Previously, the mayor of Karachi had revealed that there were no survivors. Local television showed images of a man on a stretcher and said he had survived the disaster.
Several witnesses said the Airbus A320 tried to land two or three times before crashing in a residential area near Jinnah international airport. This residential area, known as Model Colony, is a poor area with a high population density.
Karachi mayor Wasim Akhtar said at least five or six houses were destroyed in the clash. The victims were not immediately revealed among the people who live in this neighborhood.
Karachi, southern Pakistan, next to the Indian Ocean and with 16 million inhabitants, is considered the financial capital of the Asian country.
The plane from Lahore (north) was carrying 99 passengers and eight crew members, Abdul Sattar Kokha, a spokesman for the country's civil aviation authority, previously revealed.
Several witnesses that Pakistan International Airlines' Airbus A320 tried to land two or three times before crashing in a residential area near Jinnah International Airport.
The civil aviation authority also indicated that the pilot issued a distress call when indicating that he had lost an engine. I was trying to land at the nearby airport when the plane crashed.
A resident of the area, Abdul Rahman, said he had seen the plane fly at least three times, appearing to be trying to land, before crashing into several houses.
Police and the military cordoned off the area and the army said on Twitter that it had dispatched a rapid intervention force to the crash site.
The catastrophe comes a few days after Pakistan has authorized the resumption of domestic commercial flights. For more than a month, domestic calls were suspended to prevent the spread of the new coronavirus and there were rare international flights.
The worst road accident in Pakistan in recent years occurred in 2010. An Airbus 321 from the private company Airblue, flying from Karachi to Islamabad, crashed into the hills just before landing in the capital, killing the 152 people on board.
PCR (FPA / PAL) // EL
Pakistani officials indicate two survivors of the plane crash in Karachi appear first in Vision.