The same drug combination behind July's outbreak of overdoses — fentanyl and a synthetic cannabinoid, commonly known as "K2" — was found in a sample of the drug that health officials suspected caused another overdose spike over the weekend.

Health officials said the combination turned up in a sample collected from Hahnemann University Hospital on Friday — at the beginning of a surge that would eventually sicken at least 110 people and kill 7 around the city.