Wounded Pigeon in my balcony

There is a, probably wounded, pigeon (common rock pigeon) in my balcony. It is dark right now and thus, I have very little idea about its condition. But it seems it is finding it difficult to fly/move its wings because when I approached the balcony door, it 'walked' towards the farther end of the balcony while flapping its wings very slowly.

What is the right way to handle the bird and what is the best thing I can do for him/her?