An 18-year-old man has been arrested in the four-month mystery of who killed two pregnant cows in the Arizona Strip area. The Mohave County Sheriff’s Department says it arrested Briggs Roberts, 18, after he allegedly admitted to shooting two cows in December. Deputies responded to a rural area on Mt. Trumbull Loop in the Arizona Strip area on Dec. 22, where they made contact with a rancher who said two of his cows had been shot. Both of the cows were pregnant with calves, one of which was just days away from birthing. Last week, deputies received an anonymous tip identifying a suspect and vehicle description. During an interview with deputies, Roberts allegedly admitted to shooting the cows. Charges have been submitted to the Mohave County Attorney’s Office for a felony charge of killing livestock and a misdemeanor count of cruelty to animals.