Grandmothers are known for baking cookies. But ashes of grandmothers baked into cookies is a weird and disturbing twist.

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California police are investigating a claim that a high school student used the cremated remains of a grandparent in a cookie recipe and served the cookies to unsuspecting students, KXTV reported.

The sugar cookies the student brought to DaVinci High School in Davis were given to at least nine students, police told KOVR. The incident allegedly occurred on Oct. 4, KXTV reported.

"This is a weird one," Davis police Lt. Paul Doroshov told KOVR. "I have not heard of anyone getting sick or anybody being harmed as far as physically, physiologically by this."

Police are trying to confirm that the incident actually took place. Authorities said no actual evidence has been found to support the claims of students who filed the reports, KXTV reported.

"This is so unconventional, it would take more research," Doroshov told KOVR.

In a statement, the Davis Joint Union School District said the investigation is ongoing.

“This case has been particularly challenging and we have responded appropriately and in the most respectful and dignified way possible,” the statement read.