The shocking death of a 15-year-old boy from an overdose of "cheese," an amalgam of heroin and Tylenol PM, has brought local, state and federal agencies together in an investigation to find out who is supplying Dallas children with the heroin. Oscar Gutierrez, who died early in the morning of Feb. 18, was an eighth grader at Marsh Middle School. Police say his brother, who tried in vain to wake him the next morning, said Gutierrez had overdosed on "cheese" once before. Oscar’s death has sparked a cooperative effort by DEA, Dallas Police and the Dallas Independent School District (ISD) Police Force to crack down on the drug, which has killed three teenagers over the past year, according to Detective Jeremy Liebbe of the Dallas ISD Police. THE BLOTTER RECOMMENDS Photos Cheese: The Heroin for Kids Blotter Update: $2 Heroin ‘Cheese’ Spreads to Fourth Grade Click Here to Check Out the Latest Brian Ross Slideshows DEA officials in Washington and local law enforcement officials say an investigation has been launched to find out who sold the heroin to the Gutierrez. "We are pursuing all dealers," says Liebbe, who adds that if caught, the dealer who sold heroin to the young teen would be charged with murder. Law enforcement officials say they do have leads. "We suspect the same few suppliers are selling to many of the young people in the Dallas Independent School District," said Detective Monty Moncibais of the Dallas Police Force. Click Here for Photos of Cheese: The Heroin for Kids. ABC News has been following "cheese" as the use of the drug has spread among younger and younger children (some only 9 years old). Dallas police reported 71 arrests for "cheese" last year, according to Moncibais. DEA headquarters did not acknowledge the problem six months ago. Officials now say there is a problem, but it has not spread outside of Dallas. Drug counselors say "cheese" is just beginning to get the attention necessary to help them tackle the issue. Click Here for Full Blotter Coverage. "The recent death generated a rally of parents and drug enforcement authorities to try to find a solution to this overwhelming situation," says Michelle Hemm, who treats children and adolescents for "cheese" addiction at the Dallas Phoenix House drug rehabilitation center. A 14-year-old girl undergoing treatment for addiction to the drug at the Dallas Phoenix House told ABC News the kids mix up the heroin with Tylenol PM and sell the amalgam powder rolled up in notebook paper to classmates. The yellowish powdery drug resembles grated cheese.