Michael Hunn shot his children Harrison, 15, and Shelby, 13, in their beds
Credit: Facebook

On September 21, Stephanie Reece received a call that no parent wants to get. Her two children, Harrison, 15, and Shelby, 13, had not shown up to school.

When the former pro tennis player — who competed at Wimbledon and in the US Open in the Nineties — could not get a hold of her children or her ex-husband, Michael Hunn, she drove over to Hunn’s house in Zionsville, Indiana but the doors were locked and secured and nobody answered.

She knew something was wrong, so she called the police.

Officers entered the home around 10:30 a.m. and discovered Shelby and Harrison in their beds, fatally shot, and Hunn, 50, dead from a self-inflicted gunshot wound.

Micheal Hunn
| Credit: Facebook

Police believe Hunn killed his children while they slept before he turned the gun on himself.

“I can’t even imagine first of all taking anybody’s life and secondly taking my own children’s life,” Boone County Sheriff Mike Nielsen tells PEOPLE. “It is unheard of. Clearly, somebody was not in the right state of mind when he pulled that trigger.”

Nielsen says it is unclear exactly when the shooting occurred and none of the neighbors in the rural community heard any gunshots.

“It is not uncommon in our rural part of the county to hear gunshots but nobody heard anything,” he says.

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Nielsen, who declined to comment if a suicide note was found at the scene, says investigators plan to continue to investigate and search for a possible motive in the murder-suicide.

“We are going to continue the investigation and will dive deep into the history of the family and the divorce proceeding and exactly what happened there,” he says.

Nielsen says the former couple had shared visitation of the two kids and the divorce seemed relatively amicable.

“My understanding is it wasn’t a very heated divorce and they were able to work together and in fact had seen each other recently at a tennis match,” he says. “There was nothing that would have led them to believe this would happen. They were getting through this divorce that happened in November 2017 the best they could and trying to keep the kids out of it.”

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What made him kill his children might never be known, Nielsen says.

“This is one of those that unfortunately, we may never know the reason why he did this,” he says.

According to the Indianapolis Star, Reece, a girls’ tennis coach at Zionsville High and former pro tennis player, and Hunn had ongoing child custody issues.

In a petition filed in December and obtained by the Star, Reece asked for Hunn’s time with the children to be shortened and for Hunn to be screened with a blood alcohol level monitoring device, which he later agreed to.

Reece also had filed a petition in August complaining that Hunn failed to pay child support, the paper reports.

Nielsen says the murder-suicide has not only affected the community but his officers as well.

“It is a horrible tragedy for this community and it is horrible that my officers had to see what they saw and it is going to affect us for the rest of our lives because we can’t unsee what we have seen,” he says.

A funeral service is scheduled for Thursday.