Joseph Patterson, 29, has been found guilty of multiple charges in the death of Adrian Peterson's 2-year-old son
Credit: Joe Ahlquist/AP

A South Dakota jury convicted a 29-year-old man of multiple charges in the death of the 2-year-old son of Minnesota Vikings running back Adrian Peterson, PEOPLE confirms.

The Lincoln County jury found Joseph Patterson guilty of the second degree murder, first degree manslaughter and aggravated battery of an infant on Tuesday. The mother of Tyrese Ruffin, the star football player’s late son, was the boyfriend of Patterson.

“We couldn’t be more excited and thrilled for Tyrese,” Deputy Attorney General Bob Mayer said after the verdict, according to an Associated Press report. “He finally gets the justice he deserved.”

Patterson’s attorney did not immediately respond to a request for comment from PEOPLE.

The 29-year-old pleaded not guilty to the charges earlier this month, claiming that he called 911 after the toddler choked on a fruit snack. (Ruffin died two days later at a hospital). But authorities contended that Peterson attacked the boy while the two were alone in a Sioux Falls apartment, according to the Associated Press.

An autopsy concluded that Ruffin suffered four blows to the head, causing his brain to bleed. Doctors determined that the boy’s injuries were not accidental, the AP reports.

However, defense attorney Tim Rensch focused on the conflicting medical testimonies in the case, noting that some medical experts said Ruffin’s injuries were the result of choking.

“It makes no sense at all,” Rensch said, according to the Argus Leader. “Is it really possible for a man to know how to hit a kid so hard and not leave a mark?”

The jury of nine women and three men deliberated for more than five hours before finding Patterson guilty after the two-week trial.

Supporters and family of Patterson were outraged by the verdict, with some storming out of the courtroom and others cursing at the jury.

Patterson is being held at the Minnehaha County jail and is expected to be sentenced within the next two months, the Leader reports. A second-degree murder conviction carries a mandatory life sentence.

Ruffin’s mother, Ashley Doohen, cried and hugged her family upon hearing the verdict. Peterson, who faced legal troubles in a child abuse case for another one of his children following his Ruffin’s death, previously said that he learned Ruffin was his son just months before his death.

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