Pakistan International Airlines (PIA) Chairman Mohammad Azam Saigol speaks to the media at Benazir Bhutto International Airport, following a PIA plane crash in northern Pakistan, in this still frame taken from video December 7, 2016. REUTERS/ via REUTERS TV

ISLAMABAD (Reuters) - Pakistan International Airlines (PIA) Chairman Azam Saigol has resigned, citing personal reasons, the company said on Tuesday, less than a week after a PIA plane crashed killing all 47 people on board.

Officials say the aircraft suffered engine problems soon after takeoff from the mountainous region of Chitral last Wednesday, but it is not clear what caused the crash about 50 km (31 miles) from the capital, Islamabad, its destination.

“Yes, the chairman of PIA has resigned due to personal reasons,” PIA spokesman Danyal Gilani told Reuters.

Citing unidentified sources, Pakistani English-language newspaper The News said Saigol had come under pressure to resign following the crash.

Shares in PIA closed 9.16 percent lower on Tuesday at 9.95 rupees.

The media focus in Pakistan following the crash has fallen on PIA’s safety record, but the loss-making state carrier has vehemently denied media reports that there was a fault with the aircraft before takeoff.

On Monday, PIA grounded its fleet of 10 European-made ATR planes after Pakistan’s Civil Aviation Authority decided to conduct “shakedown tests” of the carrier’s entire ATR fleet.

Officials say the crashed ATR-42 aircraft, built in 2007, had racked up 18,739 flight hours since joining PIA’s fleet that year and the plane’s captain, Saleh Janjua, had logged more than 12,000 flight hours over his career.