Butler County law enforcement authorities are urging heroin users to beware of a potentially lethal batch of heroin that has hit the streets of Butler County.

Since this week, at least two overdose deaths and at least seven near-fatal overdoses have been linked to the same batch of heroin, said Butler County Detective Tim Fennell, who heads to Butler County Drug Task Force.

“Ambulance crews are getting swamped tonight,” Fennell said.

He noted that Butler Ambulance Service crews have responded to several near-fatal heroin overdoses in one shift today.

Those incidents have been reported across the county.

One of those near fatalities tonight occurred at the WalMart in Butler Township. And another occurred in the 500-block of Eau Claire Street in Butler.

Earlier today, there were two other non-fatal overdoses in the city.

Narcan, an opioid-antidote drug, has been used to halt some of the effects of the deadly batch of heroin making the rounds, Fennell said. But in many cases three, four or five doses of Narcan have been needed.

“That tells you these are not regular heroin overdoses,” Fennell said.

Authorities are so concerned about the bad batch, or stronger than normal batch of heroin, that Fennell and Butler County District Attorney Rich Goldinger put out an advisory tonight warning addicts and non-addicts about the danger.

“We want to get the word out of what we have been seeing,” Fennell said. “Addicts should know what’s out there.

“And we are warning non-addicts, ‘Don’t handle these packages or bags. We don’t know how toxic they are.’”

The bags linked to the lethal batch are light blue and have no markings on them.

“This batch seems particularly bad and particularly localized,” Fennell said.

Fennell said bags, full and empty, of the lethal heroin collected by police have been sent to the state police crime lab in Greensburgh, Westmoreland County, for analysis.

He did not know if the batch is pure heroin or has been laced with Fentenyl or some other ingredient.

“We don’t know what’s causing the problem,” Fennell said. “But it is bad and we want to identify the source.”