Pittsburgh Police Major Crimes detectives will be investigating.

PITTSBURGH (KDKA) — Pittsburgh Police are investigating after an 11-month-old girl’s death was caused by fentanyl.

The Allegheny County Medical Examiner’s Office said Mi’Orah Coleman died Aug. 19 of fentanyl toxicity.

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The report states she was found unresponsive at a home that same day on Goe Avenue in Brighton Heights and was taken to a local hospital, where she was pronounced dead.

No one has been charged with her death yet, but the girl’s father told KDKA’s Shelley Bortz on Thursday that it is his fault. Don Coleman said he used to snort the drug, but since his baby’s death, he is getting treatment.

“Th family just hasn’t been the same since the baby died,” one neighbor said. “Of course, when a little one dies, when anyone dies really, but especially a little baby, it’s just really, really hard.”

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The neighbor, who did not want to be on camera, said she woke up at 4 a.m. on Aug. 19 after hearing police sirens and an ambulance.

“He laid her down in the middle of the bed and got up to go to the bathroom or something. He came back a short time later and she was unresponsive. He screamed for his wife and they called 911,” the neighbor said.

Don Coleman told neighbors his daughter choked on mashed potatoes. On Thursday, he told KDKA he believes his daughter got ahold of the straw used to snort the drug, and that is how she died.

He said he and his wife are devastated.

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Pittsburgh Public Safety said Pittsburgh Police Major Crimes detectives will be investigating.