Animal rights activists are suing to block a federal plan to round up thousands of wild horses over 10 years in Nevada. Friends of Animals accuse the BLM of violating the National Environmental Policy Act by approving the removal of nearly 10,000 mustangs across an area near the Nevada-Utah line almost twice as big as Delaware. The suit filed in federal court in Reno says the roundup decision is unprecedented in both size and scope. BLM leaders says the horse gathers are needed to protect the rangeland from overgrazing, in an area that is carrying 10 times more mustangs than the land can sustain.