As I began painting, 2 officers (in casual attires) arrived at the spot. They didn't stop me until I reached halfway. Post which, they approached me with their respective IDs. By now, the wall owner also joined them. I tried convincing them, that, my painting is a social message on air pollution and is for a larger cause (the wall belonged to an orphanage for young boys). Unperturbed, they asked me to stop and pay up a penalty of 10,000 Rupees. "I don't have that kind of money", I blurted out.
The officer made me speak to his superior and the superior further connected me with his boss. While I was talking to them on the phone, I continued to paint with one hand as I wanted to finish my piece anyhow.
The senior officers on the phone got the meaning and context of my idea and reason to the why / what I was doing.
I convinced him and the wall owner to let me continue to paint

PS: While I was painting I didn't realize, the officers had been taking my pictures all along.