Leah Walden faces charges of first- and second-degree murder, as well as child abuse and assault.
Baltimore police said the incident happened about 3:20 p.m. Tuesday, when emergency personnel were called for a report of a baby not breathing. When they arrived, they performed CPR on the child, and she was taken to a hospital.
The baby, identified as Reese Bowman, was pronounced dead a short time later, police said.
Officials said Walden told them she fed the baby, wrapped her in a blanket and put her in a crib for a nap at the Rocket Tiers day-care facility. She told police that when she came back 45 minutes later, the girl was unresponsive.
But investigators found that video surveillance footage from cameras in the facility contradicted her story.
Police said officials at the day-care center called them Wednesday and said they had found some "disturbing video" showing Walden with the child, according to Stanley Brandford, chief of detectives for Baltimore Police.
Walden is seen covering the baby, who was awake at the time, with "excessive blankets for long periods of time," Branford said. At times, the child's face and head were covered with a pillow or blanket. Other times, the baby was violently snatched by one arm from the crib, swung and slapped.
Branford described it as torture.
Officials said it appears as though Walden was the only person who had access to the girl at the time, and had "complete care of the baby" and another child who was in the room. Police said it appears that the other baby was awake and not harmed.
The case is still under investigation.
Brandford described the case as "just evil."
On Twitter, Baltimore Police chief spokesman T.J. Smith wrote, "can't get much sadder than this. . . . "
No one answered the phone at the day-care facility Thursday, and a recorded message noted that it would be closed Thursday through Monday because of an "emergency."
Police said the center has been cooperative, noting that management found the video that led to Walden being charged.
There do not appear to be other complaints about care at the facility, police said. The center is licensed to have 60 children as young as 6 weeks, according to records from the Maryland Department of Education's Division of Early Childhood Development, which licenses centers.
The center was cited for having a building that was "not in good repair in all areas" but that was fixed, officials said. It had other citations including for using unsafe equipment, having too many children and having a "health or safety hazard" at times. But those problems were resolved, according to the state's records.
Officials said two other violations had not yet been corrected, and they had been "flagged" by the state's inspection office. Those violations involved not having proper emergency contact information for kids on hand, and the director not finishing all the continued training requirements. The center were scheduled for review in the coming weeks, officials at the state's licensing agency said.
Walden is listed as a staff member on the Rocket Tiers's website, which appears to have been taken down. An earlier taken image of the site showed Walden's bio, in which she stated that she has one year of professional child-care experience and spent six years as a part-time babysitter.
She had worked at the center for 2 1/2 years, according to police.
On the center's website, Walden said in her bio, "I love seeing the children develop new skills like sitting up, crawling and walking. The best part of being an infant teacher is caring for babies who love me as much as I love them."
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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