...........Deborah Gratz, 59, was arrested on felony charges of child endangerment Monday after police found evidence during a search of her Hollister, Calif., home.

A witness claimed to see Gratz placing a questionable substance into the drinking cups of several students, one and two-year-olds, at the Kiddie Academy preschool in Morgan Hill Friday morning, reported local Fox affiliate KTVU.

Administrators fired Gratz immediately and she admitted that the substance was Sominex, according to the school..........

Investigators are still working on Gratz's motive and whether she used sleeping aids on students before.

Anyone with information pertaining to the incident is encouraged to contact Detective Joe Burdick of the Morgan Hill Police Department. Anonymous tips may be submitted to 408-947-STOP(7867).

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