Remarks: When the plane get to the parking and before they put the chocks, a lot of smoke started to come out of the APU in the back of the plane. The masive white smoke made the fire brigade and the marshalers come. The photo was taken seconds before they turn APU off and so, smoke stoped. They had to make a quick disembark but without ramps. Fortunatelly, no big problems happened. Hours later I was told that an oil pipe broke and the smoke was the oil burning.