BISMARCK, N.D. (AP) — A national law enforcement group is lending its support to authorities who are policing the Dakota Access pipeline protest in North Dakota.

A representative of the National Sheriffs’ Association said Thursday there are sheriffs around the country who are willing to send manpower and lend their expertise.

Morton County Sheriff Kyle Kirchmeier says the protest has increased in intensity in the last couple of months and the response has “tapped the resources” of law enforcement in North Dakota. He says he welcomes the assistance.

Laramie County, Wyoming, Sheriff Danny Glick is the immediate past president of the National Sheriffs’ Association.

Thousands of people have joined the Standing Rock Sioux Tribe encampment in what has been called the largest gathering of Native American tribes in a century.