More than $3 million in marijuana was seized from an illegal grow in Hacienda Heights on Wednesday after authorities executed a search warrant.

Sheriff’s officials worked with Southern California Edison to look for unusual spikes in energy usage, which helped authorities find the illegal grow.

Officials allege the illegal grow had bypassed the utility’s panel and meter to use around $18,000 in electricity each month over several years, according to the Los Angeles County Sheriff’s Department. Authorities estimate the illegal grow stole around $500,000 worth of electricity over the years.

The Sheriff’s Department said electricity theft and illegal grows pose risks to the community, including creating fire hazards and contributing to environmental degradation.

“Today’s operation sends a clear message that criminal activity will not be tolerated in Los Angeles County,” said Capt. Glenn Emery of the Sheriff’s Industry Station in a statement. “Our communities deserve to live free from the dangers and risks associated with illegal marijuana grow operations.”

The investigation is ongoing, and no arrests have been announced.