Police used force to dispel Sundarbans campaigners today marching to Indian High Commission to hand Narendra Modi a letter against Rampal power plant.

About 400 green activists and left-leaning political activists organised by National Committee to Protect Oil, Gas, Mineral Resources, Power and Ports began the march from Jatiya Press Club at 11:00am.

Police lobbed 18 teargas canisters and sprayed hot water from a cannon to stop the march at Malibagh rail crossing. For a brief moment the activists hurled brick chips at police.

A policeman firing teargas canisters on Sundarbans campaigners as an armoured police car chases at them. Photo: Sujit Sarker

Dhaka Metropolitan Police's Ramna zone Deputy Commissioner Maruf Hossain endorsed the use of water cannon and teargas shells, and said no one was held from the spot.

Anu Muhammad, the man spearheading the campaign and member secretary of the national committee, condemned the "police attack" and declared a nationwide ‎protest for October 20.

The organisers however were allowed to send a five-man delegation to the Indian High Commission to hand over the open letter to Modi.

Leaders of Natural Committee to Protect Oil, Gas, Mineral Resources, Power and Ports during the march to Indian High Commission on October 18, 2016. Photo: Amran Hossain

Despite serious environment concerns, Bangladesh government is going ahead with plans to build Rampal power plant against protest from green and political activists.

Prime Minister Sheikh Hasina has herself tried to assure that there will be no damage inflicted on the Sundarbans. But, a different outlook has come up in research and concerns have been voiced from the Unesco as well.

Previously, a cycle rally of the Sundarbans campaigners was foiled by ruling party activists and police earlier this month.