MILLEDGEVILLE, Ga. — Investigators remained on the scene of an apparent murder and suicide in Baldwin County on Tuesday.

13WMAZ reporter Zach Merchant spoke to Baldwin County Sheriff Bill Massee for the latest on the continuing investigation and to break down what we know so far.

When first responders got to the driveway, they thought they were at the scene of a possible drowning, but what they found turned out to be much more sinister.

“It’s one of the strangest cases I’ve ever worked,” said Sheriff Massee.

According to an incident report from the Baldwin County Sheriff’s Office, deputies went to the secluded home on Watson Reynolds Road after property owner Clark Heindel called 911 to report an unresponsive woman in a hot tub in the early hours of Mother’s Day.

When deputies arrived, they found two men – Heindel and Marcus Lillard – performing CPR on UGA professor Marianne Shockley.

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Massee says the first responders thought things seemed out of place.

Detectives spoke to Heindel and Lillard before separating them. Soon after, Massee says Heindel left the porch and went back inside the home where he shot and killed himself in the master bathroom.

Later Monday, Massee announced another twist in the case.

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“Through autopsy results, we found out this was not a drowning. This is a true murder by strangulation,” he said.

Lillard was then charged with killing Shockley and trying to hide it. Massee explained the concealing charge is because Lillard allegedly made calls two hours before calling 911 asking people for advice on how to resuscitate someone.

Why didn’t they call 911 right away? Like so many other questions in the case, Massee says they’re unresolved.

“It’s a tragic event and we wish we knew all the answers,” he said.

Massee says evidence at the scene suggests alcohol was a factor in the killing. He's still waiting on toxicology reports to come back to see if drugs played a role as well.

Sheriff Massee also says they're not ruling out the possibility that Lillard killed Shockley by accident and then panicked.