The Sacramento County Sheriff’s Office is investigating a string of overdoses on a particular street in the county.

Between the week of Jan. 12 and Jan. 19, there were eight overdoses—five of which were fatal—that occurred within a two-mile stretch on Folsom Boulevard in Northeast Sacramento, according to authorities.

One victim was found Jan. 19 at Vince’s Motel, while the other seven were found throughout the week at various nearby apartments, on the same street.

Authorities say it’s currently unclear what substances the individuals took and if the overdoses all came from a single batch.

“To have so many, in a short span of time, constrained to one certain area, obviously gets our suspicions up,” Sgt. Amar Gandhi told local news station KCRA.

Mr. Gandhi said authorities suspect the overdoses could be linked to fentanyl, but that cannot be confirmed until toxicology reports are returned. He stressed the availability of Narcan for individuals partaking in illicit drug use.

He warned drug users to be aware of the risks substances pose to their health.

“If you are partaking in this type of lifestyle and you are taking some of these illicit drugs, just be aware of those risks,” he said. “Right now, our main purpose is the preservation of life.”