A Montana day care worker who worked with infants is accused of smoking meth on the job inside a "drug den" built below a cabinet.

KRTV reported that Autumn Sienna Heinz, 30, faces charges of endangering the welfare of a child, criminal possession of dangerous drugs and criminal mischief.

The suspect is accused of smoking the drugs in a “drug den” hidden beneath a cabinet in the laundry room in the YMCA Learning Center day care building.

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Police said it was locked from the inside so nobody could get in. Authorities found a glass pipe with what appeared to be meth residue and a plastic tube full of white crystals, which tested positive for meth.

The meth fumes permeated the entire building and every room tested positive for meth, including the infant room.

A vent fan in the bathroom was used to try to hide the smell of the smoke, according to police.

Heinz had been a full-time employee for three years and worked in the infant area.

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