High Desert law enforcement believe that a pregnant Marine spouse who has been missing for more than three weeks may have been shot while hunting with a Marine veteran with whom she was having an affair.

On the day she disappeared, Erin Corwin, 20, had planned to meet with her neighbor, Christopher Brandon Lee, 24, to spend a "special day together" on a hunting trip, according to documents filed in a Joshua Tree courthouse.

The day trip was meant to celebrate Corwin's pregnancy, but detectives said Lee was afraid his wife would discover their affair.

"It is highly likely that Erin could have been harmed by an unknown firearm," detectives wrote in court documents. "Sometime after Erin left with Lee, her phone was deactivated (turned off). Detectives believe if Erin was injured and left at an undisclosed location, she would not (be) able to call for help."

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