The co-pilot's name was Manjeet Kataria (not Manpreet).
According to the ATC report, there was no distress call made by the crew members..so it might be possible that the engine might have failed and because of the strong winds, dust storm and the work-load on the pilots, they hadn't got a chance to make a distress call....and finally in the wake of ontroing the aircraft, must have descended (lost control) and finally crashed....
Also one of the eye-witness says that he saw the aircraft catching up fire in the air itself, before it hit the building.
Whatever may be the reason, it is really a sad and nasty accident. May god bless the souls of everyone who lost their lives..R.I.P.