Authorities believe a body found outside Williston, N.D., is that of a missing Sidney, Mont., high school math teacher who disappeared Jan. 7 during a morning run.

Sidney Assistant Police Chief Robert Burnison said the body is likely that of Sherry Arnold. It is being sent to the state medical lab in Missoula for further identification.

Authorities told The Associated Press the body had been buried.

FBI spokeswoman Deborah Bertram said no further details would be immediately released.

Since the body was found across the state line from where the alleged kidnapping occurred, the two suspects in Arnold's kidnapping could face federal charges. Twenty-two-year-old Michael Spell and 48-year-old Lester Van Waters, Jr., both of Parachute, Colo., have pleaded not guilty to state charges.