Police were still looking Thursday night for an East Butler woman in connection with the near-death of her 9-month-old baby.

An arrest warrant was issued Wednesday for Xochitl Remedios Nopaltecatl-Rimirez, 27, who is alleged to have injured her baby Aug. 9, according to state police in the Butler barracks. She has been charged with felony aggravated assault.

Police received a call that day around 5 p.m. for an unresponsive child in an apartment on Grant Street. There they found the mother with the baby and a 3-year-old.

Nopaltecatl-Rimirez told police that around 2 p.m. the baby took a nap and after waking up, the child was bottle-fed and put on an air mattress in a bedroom. Nopaltecatl-Rimirez told police she then left the bedroom for the kitchen and she heard the baby fall.

But medical personnel, documented by police, say this explanation doesn’t account for the extreme damage done to the baby’s head.

After being flown to Children’s Hospital in Pittsburgh, the baby underwent immediate surgery for a near-fatal brain injury, court documents report.

Citing medical personnel at the hospital, police said that the baby was exposed to some kind of head impact trauma that is consistent with “repetitive acceleration-deceleration forces.” The trauma, known as shaken baby syndrome, was so severe that the baby’s injuries will likely lead to permanent impairment, documents said.

Video footage from an outing less than four hours before the 911 call show the baby was just fine, and “alert, upright and feeding,” according to police.