How Facebook 'check-ins' are used to protest Dakota gas pipeline

The Facebook check-in tool is being used en-masse to protest against the construction of the controversial Dakota Access Pipeline through land deemed sacred by Native American Indians.

Jennell Downs, with the Kickapoo Tribe of Oklahoma, puts up a flag at the State Capitol in Oklahoma City Source: AAP

More than a million people have checked-in at Standing Rock Indian Reservation, which is the site of ongoing protests against the construction of a $3.7 billion gas pipeline through the reserve considered sacred by Native American Indians.

The sudden check-in influx came following the circulation of a post which called on people to use the function at 'Standing Rock' as a way of countering what it called police "attempts to disrupt the prayer camps" by "targeting" protesters.

The Morton County Sheriff's Department responded by calling the accusations "absolutely false" in a Facebook post.

Protests, which date back to 2014, relate to the pipeline's location under the  Missouri River, the primary drinking water source for the Standing Rock Sioux, a Native American tribe of around 10,000 people.

The pipeline is a project of the Texas-based Energy Transfer Partners project, and if completed, would cross four US states.

People continue to check in from across the US and worldwide.