The mother of an 11-month-old baby girl found dead in a utility tunnel on the campus of the General Electric Company has now been charged with murder.

An autopy revealed little Halo Branton died of exposure and hypothermia, Schenectady County District Attorney Robert Carney said on Tuesday.

Persia Nelson, 24, was initially charged with second-degree manslaughter on Monday, but the charge was upgraded after the autopsy results were released, the Daily Gazette reported. The charge is now second degree murder, depraved indifference to human life, Carney said.

The baby was found eight feet down in the utility tunnel, in water up to her chest.

“The baby did not drown,” Carney said. “The baby was in the water which came up to her chest and around her head, but not her face.”

Police were initially notified that Halo was missing on Saturday night, as CrimeOnline reported.

According to the Daily Gazette, GE security found Nelson, who told them she didn’t know how she got there and that her child was missing, according to Schenectady Police Chief Eric Clifford. Security called police, who interviewed Nelson and began looking for the little girl.

After hours of searching, police issued an Amber Alert.

“As the morning came, it was also decided that we could not rule out an abduction or the child being exposed to some other dangerous situation, so we decided to put out an Amber Alert,” Clifford said.

Shortly after noon on Sunday, members of the department’s SWAT team and patrol officers found the missing girl in the utility tunnel. She was rushed to Ellis Hospital, but medics and doctors were unable to revive her, and she was pronounced dead at 1:24 p.m.

Nelson was arraigned and given a $500,000 cash bail. She was scheduled to return to court on Thursday, but that could be delayed because of the upgraded charge, Carney said, as prosecutors are taking the case “to the grand jury expeditiously.”

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[Featured image: Halo Branton/Schenectady Police Department]