Over the Fourth of July weekend, a batch of fentanyl-laced drugs left nine people dead of apparent overdoses in Gadsden County, Florida, the Tallahassee Democratreports.

Local officials put out an alert about the laced drugs on Friday, after two women were found dead of apparent overdoses. “Here in Gadsden, I have not heard of any opioid poisoning here in the county as it relates to fentanyl,” said Sheriff Morris A. Young. “But on Friday, it was very apparent that it was here in the county, and we had about 15 calls related to it.”

Officials said that seven deaths connected to the supply of drugs have been confirmed so far, with two other deaths pending investigation. The oldest to die was a 60-year-old woman, while the youngest was a 34-year-old man. Gadsden County authorities are currently working with the U.S. Drug Enforcement Agency on the matter.

“Today we learned of another potential mass fentanyl poisoning event in Gadsden County, Florida,” DEA administrator Anne Milgram said in a statement. “We send our deepest condolences to the multiple families involved. This tragedy demonstrates yet again the extreme danger of fentanyl, which we continue to seize in all 50 states, often hidden in other drugs or made into fake pills. The men and women of the DEA are committed to bringing to justice the criminal drug networks and dealers that are killing Americans by deliberately distributing fentanyl and deceptively mixing it into other substances and into fake pills.” 

Fentanyl, a powerful opioid typically used for pain medication, has heavily impacted the illegal drug market in the United States. It has often been cut with other drugs to increase potency, and has proved to be very dangerous. Back in May, the Louisville Metro Police Department launched an investigation into a drug bust where officers allegedly uncovered enough of the drug to kill four million people.