1 / 4   Local cameraman Azim Khan Ronnie from Bangladesh documented the huge scale of the brick making industries with a drone to reveal the extent of algae spread creating a serious pollution problem in Bangladesh. /VCG Photo

2 / 4   The breathtaking scale of Bangladesh's brick making industry's release of harmful chemical elements, which make the growth of algae spread in the country’s river can be seen through these aerial photographs. /VCG Photo

3 / 4   Brick making creates heavy air pollution and it is estimated that one million people churn out a staggering tens of billions of bricks each year across 7,000 separate kilns. /VCG Photo

4 / 4   In the capital of Dhaka, with the increasing of pollution from brick factories and dyeing plants, water in the River Turag has turned green. /VCG Photo