CARSON CITY, Nev. (AP) — The U.S. Bureau of Land Management has announced new rules restricting the private sale of wild horses and burros. The rules announced Friday are in response to an investigation of a Colorado livestock hauler who has bought more than 1,700 horses since 2009. The Department of Interior's inspector general is investigating whether any of the horses sold to Tom Davis were taken to slaughter.

Wild horses are protected under federal law, and selling them for slaughter is illegal. Davis has denied any wrongdoing. Sales of wild mustangs and burros will be limited to no more than four within a six-month period unless prior approval is obtained from a BLM assistant director. Buyers also must describe where they intend to keep the animals. About 37,000 wild horses roam Western states. About half are in Nevada.