Crystal Czyzewski was charged with first-degree manslaughter and risk of injury to a minor in the death of her son, according to Connecticut State Police.
Authorities said EMS personnel responded to a home in the New London County town of Griswold after receiving a report from Czyzewski at about 9:30 p.m. on Wednesday, Nov. 17.
Police said Czyzewski had called to report that her baby was unresponsive.
The baby was taken to the Connecticut Children's Medical Center, and he received medical treatment for several days, police said.
He was pronounced dead on Sunday, Nov. 21, authorities said.
According to a warrant for Czyzewski's arrest, Czyzewski eventually told authorities that she had put a blanket over the baby's head and placed her hand over the blanket and the baby's face for 20 minutes until he stopped breathing.
Authorities said Czyzewski also admitted to leaving the baby in the residence for most of the day before calling the police.
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