A Milwaukee man, 53, allegedly used a sledgehammer to murder his 12-year-old grandson after he found money missing from his wallet.

The accused, Andrez Martina, also used a coat rack and mallet to thrash the boy for at least 90 minutes, reported Fox News. He is facing multiple charges including first-degree intentional homicide and physical abuse of a child.

Nekeda Martina, the mother of the victim, Andre Smith II, can't believe that her child is gone, and described her son as kind, and "sweet as pie," according to FOX 6 Milwaukee.

On Sunday morning, cops responded to Children's Wisconsin to investigate a child abuse complaint. When they reached the spot, the boy was found unresponsive and was taken to the emergency department. Almost an hour later, doctors declared the boy dead.

During an interaction with cops, the legal guardian of the child indicated Andrez asked that his grandson and an eight-year-old boy sleep over at his house. Around 8.25 am on Sunday, he sent a text message accusing his grandson of stealing cash from him.

According to a criminal complaint, when the guardian asked Andrez where the boy was, he said, "He's bleeding." Then the child's mom was immediately asked to go to Andrez's house to check on the boy. He suffered a severe skull fracture, said the Milwaukee County Medical Examiner's Office.

The great-grandmother of Andre Smith II told police that she was "awakened by the defendant yelling" at the boy, and that she "saw the defendant striking (the boy) with a hammer."

On Monday, the accused told police detectives that after returning to Milwaukee from Indiana, he "wanted to reconnect with his grandchildren." Andrez learned that the 12-year-old boy had a problem stealing, and he recalled telling his grandchildren in the past, "If you lie, if you mess up in school, if you steal, I'm going to kill you."

He told police that on the day of the incident, he woke up and "noticed that his wallet was open and money was missing." He then went to the living room to confront the 12-year-old about the missing money. On confrontation, he "smacked" the child repeatedly, and demanded that he get his money. To protect himself, Smith II ran into the bathroom and locked himself inside, but then his grandfather picked the lock open and "lost it" on the child.

This isn't the first time that Andrez has committed a crime. He admitted to cops to murdering a boy in 1989. Nekeda said, "My dad killed somebody in 1989. The system failed to stop him from doing that again. Unfortunately, his last victim was my child."

A teenage girl along with her 37-year-old boyfriend has been accused of brutally killing her parents with a hammer and a pressure cooker after they objected to the suspects' marriage in Jamshedpur, Jharkhand, India on Sunday, Aug. 7. This is a representational image. Grieslightnin/ Pixabay