Dozens of people have been treated in Connecticut during the past two days after officials say they overdosed on K2, an often-laced synthetic drug.

As of Thursday afternoon, emergency crews had responded to more than 90 overdose cases in two days, most from a park in downtown New Haven near Yale University.

New Haven Fire Chief John Alston Jr. had to stop in the middle of a press conference about the spike in overdoses Wednesday after getting a call about another overdose.

The mayor's office says DEA test results confirmed samples of the drug were a form of K2 or "spice," a cheap, synthetic cannabinoid.

K2 can be anywhere from two to 100 times more potent than THC.

“It’s made informally, so it can be all different kinds of chemicals. Frequently, it's laced with other things,” says Sandy Bogucki, EMS medical director.

Because of that, officials say buyers have no way to know what they are purchasing. 

“We are searching and executing search warrants at additional locations to make sure that any additional product that may be out there that we can get in to our custody,” says New Haven Police Chief Anthony Campbell.

No one has died from the overdoses in Connecticut, but in April two people died in Chicago from a bad batch of K2 that caused severe bleeding in 54 other people.

In May, K2 caused dozens of people in Brooklyn to be hospitalized. In July, D.C. officials say about 300 people overdosed on the drug in a two-week span.