The closure and arrest happened Wednesday at Bina's Family Child Care in La Crescenta after the girl was hospitalized Tuesday night, the Glendale (Calif.) Press News reported.
Glendale Police Sgt. Tom Lorenz said that the girl's parents dropped her off Tuesday morning and picked her up that evening to discover she was lethargic. When her condition did not improve, the parents brought the girl to a hospital where she tested positive for THC, an active ingredient of marijuana, Lorenz said.
The parents then told police they believed their daughter "consumed" marijuana at the daycare center, Lorenz said.
On Wednesday morning, police arrived at the day-care center and waited for director Roubena Hartounian, 50, to arrive.
Officers obtained a warrant and searched the facility. During the search, they found non-functioning toilets, dirty dishes and knives in the kitchen, and rat and mice droppings throughout the facility, including on children's toys, Lorenz said. Investigators said they also found drug paraphernalia.
"The conditions of the home warranted a criminal investigation," Lorenz said.
Hartounian was arrested on suspicion of child neglect and endangerment at her residential day care.