How this river turned into this colour in China?

People in China were astounded after citizens encountered a strange blue river in Dongguan as officials are trying to figure out what has led to the change in the colour of the water, reported Asia Wire.

Residents of the nearby river believed that the change was because of the adjacent petrol station that was dumping out chemical waste.

The cameraperson who shot the footage claimed that the filter was not applied to the video and it was natural.

"It’s not special effects; I’ve never seen anything like it," the cameraperson who shot the video was quoted by Metro UK as saying. However, he also claimed that after some time when he returned to the river, the colour of the water turned normal.

According to other reports, the colour of the water changed because the employees from the nearby delivery point dumped colour into the water, however, it remains unconfirmed.

The officials of the Dongguan Ecological Environment Bureau are on the river site to run testing, according to Metro UK.

A similar thing happened earlier this month in Chicago as the city’s River was dyed green for St Patrick's Day.

It is done every year by the Chicago Plumbers Union.

"Their environmentally friendly dye formula remains a closely kept secret," Choose Chicago a plumbers union, Choose Chicago was quoted as saying by NBC Chicago.