Pakistani search and rescue teams have recovered the flight data recorder and cockpit voice recorder from the debris of Bhoja Air Boeing 737-200 that crashed on the night of 20 April.
They have been handed over to the Civil Aviation Authority of Pakistan (CAAP), says local news reports.
Farouk Omar Bhoja, the airline's chairman and chief executive, has been barred from leaving the country and placed in protective custody as investigations of the country's second-worst air disaster begin.
Bhoja Air has confirmed that all 121 passengers and six crew members on board died in the incident. The aircraft was on a scheduled service from Karachi to Islamabad when it crashed roughly four miles from the capital's Benazir Bhutto International airport.
There was bad weather with heavy rain and a low cloud ceiling at the time of the incident, although the head of the CAAP was quoted in local newspapers as saying that another aircraft landed safely five minutes before the crash.
The 737-200, which had the registration AP-BKC, was built in November 1984 and entered into service with British Airways in 1985. It was subsequently owned by Comair, which parked the aircraft in January 2011. Bhoja Air bought it in January 2012 and it entered into service with the airline on 3 March.
The Karachi-based airline only resumed operations in March after suspending services for several years because of financial difficulties.
The airline has one more 737-200 in active service and another 737-200, a 737-400 and a Boeing DC-9-30 in storage, according to Flightglobal Pro data.
Pakistan's worst air crash took place on 28 July 2010, when an Airblue Airbus A321 crashed into high terrain during a bungled circling approach into Islamabad. None of the 146 passengers and six crew members survived the incident. Investigators said that the captain's arrogance and poor airmanship was the main cause of the incident.