For months, protesters have stood in the path of an oil pipeline that is under construction near the Standing Rock Sioux Reservation, which straddles North and South Dakota.
The Standing Rock Sioux tribe has opposed the construction of the Dakota Access pipeline since it was first proposed in 2014.
Demonstrations began in April with a handful of people praying in a camp on the reservation, and have since grown to include hundreds, sometimes thousands, of activists.
As the protests continue, here's a quick overview of the situation by the numbers.
1,172 miles: The length of the proposed Dakota Access pipeline
The pipeline, slated to stretch across 1,172 miles at 30 inches in diameter, would carry hundreds of thousands of barrels of crude oil a day through 50 counties in four states — from western North Dakota through South Dakota and Iowa, ultimately connecting to an existing pipeline in Patoka, Ill.
The pipeline would travel under a dammed stretch of the Missouri River that borders the Sioux reservation in North Dakota. Native American groups say the construction would desecrate sacred sites and could ruin the reservation's drinking water supply.
470,000: The number of barrels of oil that will be transported a day through the completed pipeline
That amount of crude oil would produce enough gasoline to drive a medium-sized car from Los Angeles to San Francisco more than 330,000 times.
The pipeline's capacity is even higher, according to the developer. When completed, it could pump up to 570,000 barrels of oil a day.
8,000 to 12,000: Local jobs the pipeline developer said would be created during construction
According to Texas-based developer Energy Transfer Partners, construction of the $3.78-billion pipeline would create between 8,000 and 12,000 local jobs, including those for welders, mechanics, electricians, pipe-fitters and heavy equipment operators.
More than 300: Tribal nations that oppose the Dakota Access pipeline
More than 300 tribal nations have come out against the Dakota Access pipeline and pledged their support for the Standing Rock Sioux Nation.
About 800: The number of people demonstrating against the pipeline now
Standing Rock Sioux tribal leadership said Monday that there were 800 people on the site acting as "protectors" — the term they prefer to use for those opposing the pipeline's construction.
But tracking the number of protest participants is difficult, as people come and go periodically. In recent months, thousands of tribal members and environmental activists have gathered at the proposed site of the pipeline. Appearances from celebrities such as actress Shailene Woodley and actor Mark Ruffalo have helped bring the protest to the national spotlight.
412: The number of protesters arrested as of Sunday
What began in the spring as a peaceful demonstration ramped up Aug. 11, when protesters marched onto the construction site and blocked workers from building, said Morton County Sheriff's spokesman Rob Keller.
That day, he said, 13 people were arrested.
"You cannot march onto and hinder, go on private property and stop construction — that's against the law," Keller said. "The Dakota Access pipeline had all the easements, and all of the requirements, so they could legally be there."
Since then, hundreds more have been taken into custody on various charges, including criminal trespassing, engaging in a riot and conspiracy to endanger by fire.
Tensions between police and demonstrators escalated last week, according to the Sheriff's Department, with protesters throwing Molotov cocktails at officers and setting cars on fire on the Highway 1806 bridge, prompting its closure. One woman fired a gun at officers, police said, though no one was struck by gunfire.
Activists said police fired rubber bullets at protesters and detained them in what appeared to be dog kennels.
"Militarized law enforcement agencies moved in on water protectors with tanks and riot gear today," Dave Archambault II, the chairman of the Standing Rock Sioux, said in a statement Thursday. "We have repeatedly seen a disproportionate response from law enforcement to water protectors' nonviolent exercise of their constitutional rights."
At least 1.3 million: The number of Facebook users who ‘checked in’ to the Standing Rock Indian Reservation online
At least 1.3 million people had "checked in" to the Standing Rock Indian Reservation on Facebook as a show of support for activists trying to block the pipeline, after one user claimed that authorities were tracking protesters on social media. The Sheriff's Department said Monday that the claim was "absolutely false."
$4 million: The amount of additional funding that authorities have requested to cover costs associated with the protests
The office of North Dakota's highest-ranking military officer, the adjutant general, has requested an additional $4 million to continue covering public safety costs associated with the demonstrations. The state's Emergency Commission — made up of the governor, secretary of state and four legislators — is expected to sign off on the request Tuesday. The funds would add to the $6-million line of credit approved in September, most of which has been used, Secretary of State Al Jaeger said.
"Right now the first purpose is to protect property and people," Jaeger said Monday. "We have no choice but to provide the funding."