PORTLAND, Ore. (AP) - The same day seven defendants were acquitted in the armed takeover of a federal wildlife refuge in Oregon, law enforcement officers in riot gear arrested nearly 150 oil pipeline protesters camped out in North Dakota.

The developments have drawn a sharp contrast for many between the treatment of mostly Native American citizens near the Standing Rock Sioux Reservation and the heavily armed Oregon occupiers who held off the federal government for weeks.

Experts say the protests are ideologically far apart but share broad themes. Both groups feel they're marginalized and are fighting to protect what, to them, is a sacred way of life.

But Native Americans in Standing Rock say that's not enough to discount what they call the environmental racism that led to the arrest of 141 protesters Thursday in North Dakota. That's the same day the leaders of the Oregon standoff were acquitted.

Related: Juror, federal officials, lawyer react after not-guilty verdict