The number of overdose cases on Chicago's West Side has jumped from more than 20 in 24 hours to more than 70 within 72 hours. 
 
 Chicago Fire Department spokesman Larry Langford said there has been 74 overdoses in the past 72 hours, noting that the number is more than double the rate of overdoses the city saw at this time last year. 
 
 Chicago authorities said Thursday they were investigating what's behind the spike. 
 
 A Chicago Department of Public Health alert obtained by the Tribune reported more than 20 people had overdosed in the neighborhood in just 24 hours. 
 
 Police recovered a sample that may have been heroin laced with the painkiller fentanyl purchased at two West Side locations. Langford said it was not clear how much fentanyl had been added to the heroin batches. 
 
 Chicago Police News Affairs on Friday said that 23 overdoses were reported in 24 hours, but no one had died as of Friday afternoon. 
 
 Police said multiple law enforcement agencies were working "to identify the source of the extremely strong batch of heroin." 
 
 The painkiller was in the spotlight in the in the mid-2000s when dozens of people died from fentanyl-related overdoses. ||||| By Friday afternoon, 14 people had been rushed to Mount Sinai Hospital in Chicago in the previous 24 hours to be treated for heroin overdoses, some with the needles still stuck in their arm, according to hospital officials. 
 
 In all, nearly 75 people have overdosed in Chicago since Tuesday afternoon from dangerous batches of narcotics, possibly heroin laced with the painkiller fentanyl, according to city health and fire officials. Police were investigating if at least one recent death was caused by a heroin overdose. 
 
 "We suspect what is happening is the same thing that happened in 2006 when people were getting heroin that was cut with fentanyl, which is a very strong narcotic," said Diane Hincks, a registered nurse and emergency room director at Mount Sinai on the West Side. "That's what we think is happening." 
 
 By early Friday afternoon, emergency crews had responded to 74 cases over 72 hours, more than double the same three-day period last year, said Larry Langford, spokesman for the Chicago Fire Department. 
 
 Hincks said some of the 14 overdose victims treated at Mount Sinai had collapsed as soon as they injected themselves. The hospital typically sees two or three overdoses a day, she said. 
 
 Two of Mount Sinai's patients were in intensive care, another was still undergoing treatment, seven had been discharged and a few more were still in the emergency room as of about 3 p.m, Hincks said. 
 
 Chicago police said the drugs were purchased primarily at two locations on the West Side, one of them in the North Lawndale community. A sample of heroin recovered by police may have contained fentanyl, authorities said. 
 
 The Drug Enforcement Administration is working with Chicago police to try to find the source of the dangerous batches of drugs. 
 
 At City Council budget hearings Friday afternoon, Chief Mary Sheridan, head of the Fire Department's emergency medical services division, said all the recent overdose victims were stabilized with a single dose of Narcan, a heroin antidote carried by Chicago paramedics, and then transported safely to hospitals. But fire officials said the victims required additional doses of Narcan after arriving at hospitals. 
 
 "They're taking double and triple the doses of Narcan in order to bring them out of their stupor," Hincks told the Tribune. 
 
 Paramedics and other Fire Department personnel were given extra Narcan for their medical runs, officials said. 
 
 Chicago police, meanwhile, are looking into whether a 49-year-old man who died of an apparent drug overdose in the West Side's East Garfield Park neighborhood had ingested narcotics from one of the dangerous batches, according to law enforcement sources. 
 
 Heroin overdoses are spiking in Chicago. Authorities think the illegal drug may be spiked with something. Oct. 2, 2015. (CBS Chicago) Heroin overdoses are spiking in Chicago. Authorities think the illegal drug may be spiked with something. Oct. 2, 2015. (CBS Chicago) SEE MORE VIDEOS 
 
 The victim was found dead in a third-floor apartment Thursday night in the 3300 block of West Ohio Street, police said. An autopsy on the victim Friday was inconclusive, pending toxicology studies that could take up to eight weeks to complete, according to a spokesman for the Cook County medical examiner's office. 
 
 The Chicago Recovery Alliance, which helps drug users, trains the public in overdose prevention, provides HIV testing and conducts needle exchanges, urged caution. 
 
 "The best thing would be to have (Narcan)," said Dan Bigg, the group's director. "And watch each other's backs." 
 
 Fentanyl-laced heroin has been causing overdoses across the nation. The DEA issued a nationwide health alert in March. 
 
 Dr. Steven Aks, chief toxicologist at Stroger Hospital and an emergency physician, said fentanyl is used for especially painful surgical procedures. 
 
 The powerful synthetic painkiller adds a potent kick to heroin, making it attractive to suppliers seeking an edge with customers. 
 
 The last major outbreak of fentanyl-related deaths took place between 2005 and 2007, killing more than 1,000 people across the country. Dozens in the Chicago area died of overdoses, including from fentanyl mixed with other drugs. 
 
 Hincks recalled how busy Mount Sinai's emergency room was for a few weeks in 2006, when she was a charge nurse, because of the fentanyl-laced heroin. 
 
 "I remember how crazy it was," she said. "It got to the point it was just full. We had everyone lined up in the halls on carts. ... It was very busy." 
 
 Cristina Villarreal, a spokeswoman for the Chicago Department of Public Health, said that by 8:30 a.m. Friday more than 20 people had been treated for heroin overdoses. Villarreal said the department was awaiting lab results to confirm if the heroin was laced with fentanyl. 
 
 "We are working closely to ensure that area hospitals are tracking individuals affected and are maintaining a necessary stock of medication supplies — including Narcan," Villarreal said in an email. 
 
 John Callahan, coroner of Grundy County, said his office has seen three heroin-related deaths in the Morris and Coal City areas this year — but all of them came in August. 
 
 He said he had been contacted by the DEA about two weeks ago. 
 
 "They're trying to trace back where this potent heroin came from," Callahan said. "The way I understand it, there's a bad batch.'' 
 
 Heroin overdose deaths have been on the rise statewide since 2011, according to data from the Illinois Department of Public Health. Last year, 633 heroin overdose deaths occurred in Illinois, up from 583 in 2013. In Cook County, heroin overdose deaths remained largely unchanged last year at 283, down eight from 2013. 
 
 A recent Roosevelt University report concluded that the Chicago area is racking up more heroin-related emergency room visits than any other metro area in the country. Compounding the problem was that state-funded drug treatment had dried up, the report found. 
 
 Illinois' heroin crisis has drawn increasing attention from government officials in recent years, and lawmakers have proposed numerous measures aimed at attacking the problem. 
 
 Chicago Tribune's John Byrne and The Washington Post contributed. 
 
 jgorner@tribpub.com 
 
 pnickeas@tribpub.com 
 
 rsobol@tribpub.com
– Chicago authorities are scrambling after 74 heroin overdoses were reported in the 72 hours between Tuesday and Friday afternoon, more than double the overdose rate during the same time last year, NBC Chicago reports. Police suspect an "extremely strong batch of heroin" that's been laced the powerful painkiller fentanyl. They are currently hunting for the source of the drug, which appears to have been sold at two locations on the city's West Side. "We suspect what is happening is the same thing that happened in 2006," Mount Sinai emergency room director Diane Hincks tells the Chicago Tribune. Between 2005 and 2007, more than 1,000 people around the country died from fentanyl-laced heroin. The Tribune reports there have been no deaths during the rash of overdoses this week that can be definitively traced to heroin laced with fentanyl, though authorities are waiting on toxicology reports from a 49-year-old man who died of an apparent overdose Thursday. Hospitals are supplying paramedics with extra doses of Narcan, a heroin antidote, due to the strength of the current batch. "They're taking double and triple the doses of Narcan in order to bring them out of their stupor," Hincks tells the Tribune. The DEA issued a nationwide warning about fentanyl-laced heroin in March. A recent study show Chicago has more heroin-related ER visits than any other US city.