BENZIE COUNTY, MI -- An 18-year-old woman admitted to police that she "freaked out" after giving birth in a campsite tent and struck the newborn with her closed fist, a northern Michigan newspaper is reporting.

The baby girl died the next day at a hospital.

The Traverse City Record Eagle is reporting that Alyce Morales of Cicero, Ill., "made several admissions" to state police that she caused the infant harm.

The baby was born shortly after 11 p.m. July 22 in a tent at the Platte River Campground in Benzie County.

Morales was at the campground with her parents. They did not know she was pregnant, police said.

The Record-Eagle obtained court documents that offered details of a police interview with Morales. Detectives said they learned she kept her pregnancy secret.

“Alyce did not want to tell her parents for fear of disappointment,” a detective said in the documents.

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Morales reportedly went to the family's tent after telling her parents she felt ill. She then gave birth.

Her father soon after walked into the tent and found Morales with the newborn. Police said the baby already had been injured at that point.

The baby was taken to Munson Medical Center, where she died the next morning. But an autopsy in Grand Rapids showed "serious injuries" to the child's head and abdomen, the Record Eagle reported.

Morales, charged with open murder, is held in the Benzie County Jail without bond.

E-mail John Tunison: jtunison@mlive.com and follow him on Twitter at twitter.com/johntunison