Imam once told me: Once, Shah regime's agents busted into my house, arrested me, and took me towards Tehran. On the Qum-Tehran road I told them it was the time for the Fajr prayers and I asked them to stop at a place where I could do wudhu.
They replied that they did not have permission to do so. I said to them, you are armed and I am weapon-less. I won't be able to do anything. Again they said that they did not have permission.
I knew it was pointless and they would not stop the car. I said, At least stop for a while so that I can do tayammum by the side of the road.
In the end, they stopped the car. However, they did not let me get down.
Whilst still sitting in the car, I bent down and did tayammum. I then said my prayers with my back facing Qibla. That day I said my prayers with tayammum, my back towards Qibla, and in a moving vehicle. Perhaps those two rakat prayers will achieve Gods pleasure.