Updated

A California day care worker has been arrested after she was allegedly caught dropping sleeping pills into children’s drinks before naptime.

A witness told police that Deborah Gratz, 59, put the over-the-counter sleep medication Sominex into several cups at the Kiddie Academy Childcare Facility in Morgan Hill on Friday. Gratz later admitted what she did to the day care’s administrators, the Silicon Valley Mercury News reports.

"We are still investigating to try and determine if this has been going on for some time," Morgan Hill Sgt. Troy Hoefling said.

Gratz, who has worked at the day care for the past five years and had a class of 1 and 2-year olds, was fired Friday and arrested on Monday on suspicion of child endangerment.

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