(CNN) — A 2-year-old son of Minnesota Vikings star Adrian Peterson is in critical condition Friday after allegedly being abused in South Dakota, the running back's father told a Minnesota newspaper.
Sioux Falls, South Dakota, police said Joseph Patterson, 27, has been charged with aggravated battery of an infant and aggravated assault.
Patterson called authorities about 5:45 p.m. Wednesday to a report that a 2-year-old was choking in his Sioux Falls apartment, police spokesman Sam Clemens said. Officers arrived to find that the toddler was unresponsive, and he was rushed to a local hospital.
Authorities determined that the child had suffered injuries consistent with abuse, including to his head, according to Clemens. Police said Patterson, whom they described as the boyfriend of the injured child's mother, was the only other person in the residence at the time.
The suspect was arrested the following day, said Lincoln County, South Dakota, State's Attorney Tom Wollman. A judge set his bail at $750,000 cash during his court appearance Friday, according to Clemens.
The 2-year-old, meanwhile, remained in critical condition at a South Dakota hospital on Friday afternoon, the police spokesman said.
His mother is not under investigation, Clemens added.
Adrian Peterson's father, Nelson Peterson, told the St. Paul Pioneer Press that the injured toddler is his grandson and Adrian's son. Nelson Peterson did not identify the boy by name except to say he is not Adrian Peterson Jr.
The NFL standout himself did not elaborate on what happened when addressing reporters Friday, though he did acknowledge that he was dealing with "a private matter," adding that he still plans to play in Sunday's game against the Carolina Panthers.
"I will ask you all to please just respect my privacy," Peterson said.