A batch of illicit drugs that was mixed with fentanyl and other substances may have been the cause of a mass overdose in.

Five people in Baltimore were hospitalized for a reported overdose incident, one week after 27 were sickened in the same area of the city, police said.

Federal scientists from the National Institute of Standards and Technology have identified a combination of substances believed to be responsible for last week’s mass overdose in Baltimore’s Penn North neighborhood.