Sean A. Flowers Jr., 25, has been arrested after he allegedly drowned his 3-month-old son in a pond.

According to witnesses, Flowers took the child to a pond after an argument with the child’s mother, who is his girlfriend, during a family reunion. He sat down and simply held the child under even as the baby screamed.

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“Without thinking, I just ran into the water. I yelled at him ‘where’s the baby? Where’s the baby?’ And then I saw a baby floating in the water,” witness Joey Griffin told Fox 6 News.

“I grabbed it. I tried to swim away with it. He lunged at me and took the baby again and swam further, deeper. We all lost this one. No matter what you do, no matter how hard you try, sometimes you just lose. No matter how hard you try. You just wish you could’ve did more.”

Another witness, Robert Amstadt, said it was “the most evil thing I’ve seen.”

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“That baby cried all the way out into the water,” Amstadt told the Journal Sentinel. “Then the crying stopped.”

Amstadt said that people crowded around the pond were panicked at the sight and that the scene “was a hornet’s nest of people moving around, crying and screaming,”

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Fox 6 News reports that boy’s mother has another child with Flowers and filed a temporary restraining order against him last April, but the order was dismissed when she didn’t show up in court.