Police were investigating Thursday to find out what happened to a Missouri emergency room doctor who went missing only to turn up dead with an apparent gunshot wound in an Arkansas lake more than a week later.

Dr. John Forsyth, 49, was last seen on May 21 and didn’t show up for his shift in the Cassville, Missouri hospital where he worked. His body was discovered by a kayaker on Tuesday in Arkansas, authorities said. What happened to him in between is still largely a mystery.

His family members said in interviews and on social media that Forsyth was dedicated to his job and never would have missed a shift. His brother, Richard Forsyth, told news outlets that the doctor even sometimes slept in an RV parked near the hospital so he wouldn’t miss a call about one of his patients.

Here’s what we do and don’t know about Forsyth’s disappearance and death:

Where and when did he go missing?

Forsyth showed up to the hospital in Cassville, a small town of about 3,100 residents in the Missouri Ozarks, the morning of May 21. He texted his fiancée that morning at about 7 a.m., and said he would see her later, his brother Richard Forsyth told CNN. He stopped replying to messages after that.

He didn’t show up for his afternoon shift, his brother told The Daily Beast.

“He wouldn’t miss a shift even if his eyeballs were hanging out of their sockets,” Richard Forsyth told The Daily Beast last week. “It was an immediate red flag.”

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