NUNN — A Texas 18-year-old was charged with first-degree murder Friday in the stabbing of her baby after giving birth on her own while visiting Colorado with family, prosecutors said.

Leiyla Cepeda told an investigator the baby was quiet and not moving and did not seem to be breathing when she was born but declined to explain why the baby had stab wounds, according to court documents. In an interview with her mother present, Cepeda said she thought she had been pregnant but was not sure, explaining that a pregnancy test she had taken about three to four months before was negative.

A coroner determined the baby was alive when born at the home of Cepeda’s relatives in the small town of Nunn and died of multiple sharp force injuries, according to Cepeda’s arrest affidavit. A pair of scissors was found near the baby’s body, the document said.

It was not known if Cepeda, who has been hospitalized since giving birth, had a lawyer yet.

She was 17 when the baby was born but turned 18 on Friday, Krista Henery, a spokesperson for 19th Judicial District Attorney Michael Rourke, said. She has been charged as an adult.

While being questioned, Cepeda was asked what she was thinking when the baby was born, according to the arrest affidavit. “She stated she had to figure out how to tell her mom,” the investigator wrote.

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