Update 1:00 A.M.:

As of 1 A.M. 100 to 200 protesters remained at the Backwater bridge with about a dozen fires reported at the location. Meanwhile, protesters claim they were being hit with rubber bullets.

There are no reports of injuries that can be verified.

Update 8:57:

Authorities say about 400 protesters clashed with police tonight along the Backwater Bridge on Highway 1806 in Morton County.

Law enforcement says that as of 8:30 this evening, protesters attempted to start several fires.

Officers also say demonstrators have been aggressive, attempting to flank and attack the police line.

Police say they've used less-lethal means to stop the protesters from crossing the bridge, including using tear gas.

Original Story:

Authorities say 300 protesters have gathered along the Backwater Bridge on Highway 1806.

The bridge has been the site of previous clashes between police and demonstrators.

Dallas Goldtooth, Keep It In The Ground Campaign Organizer, says in a Facebook post protesters went to the bridge to remove a blockade that has been in place since October 27.

We're working on gathering more information. This story will be updated as it comes in.

UPDATE 8:57: Officers also say demonstrators have been aggressive, attempting to flank and attack the police line.... Posted by KFYR-TV on Sunday, November 20, 2016