Damaged to my car.

On 20:30 27/08/2015 a parked my car at the parking of international drop off zone to drop my friend, I went to the toilet which took me - 5 minutes.When I came back their tow truck guys were about to tow away my car. I tried to explain to them that I was away just for -5 minutes. I begged them to not tow the car as I did not know that I was not supposed to get off the car.They refused, They did not introduced themselves and I could not trust them, I even asked to go with them when they tow the car as I had valuable things in my car they also refused and just wanted to tow the car and leave me behind alone. They could even see the boxes inside the car through the window. I opened the car and sit inside while they towing the car.They towed the car while I was sitting inside. When we arrived at the yard, I got off the car and called the person I dropped off to tell him that my car has been towed, I gave the tow truck guy the phone to speak to the person. While he was talking on the phone, he put down my car, When I looked at the car, it was rolling down towards the pavement, he was not even aware that the car was rolling, the car hit the pavement and damaged. I have been told to wait.