(McMinnville, OR)  --  The principal of a middle school in McMinnville says the school received an anonymous phone call of a threatening nature.  Patton Middle School Principal Brian Crain told KATU-TV the call was traced back to an elementary school in Salem, but it's believed the call was a prank.  Brookwood Elementary School in Hillsboro was reported to have also received a threat, but it's not known whether it's connected to the McMinnville threat.