The Colorado Bureau of Investigation says the water supply of the Town of Hugo has tested negative for THC, immediately lifting the water advisory set in place.

The town of Hugo’s approximately 720 residents were warned not to drink or cook using the local water supply after authorities found evidence of THC.

Cpt. Michael Yowell with the Lincoln County Sheriff’s Office says investigators have found evidence that someone may have tampered with one of the town’s five wells.

A criminal investigation regarding tampering and forced entry at Hugo's Well #1 will continue.

The Lincoln County Sheriff’s Office was first told about the issue with the town’s water supply on Thursday afternoon. Hugo Public Works first learned about it after, while trying to administer a drug test, an employer in the area noticed that the town’s water was positive for THC.

This prompted additional tests, and Yowell says the sheriff’s office was able to isolate the THC to one well – Well #1. CBI scientists believe the test kits were a false positive.

The Lincoln County Sheriff’s Office will release more information on the investigation as it becomes available.