 A Spirit Airlines pilot and his wife found dead by their children in March in their Ohio home overdosed on a lethal combination of cocaine and carfentanil, a powerful derivative of fentanyl often used to tranquilize rhinoceroses and elephants, PEOPLE confirms. >> NEW: ‘Speedball’ use by Centerville pilot not first at Spirit Airlines 
 
 >> EARLIER: Couple’s death may be fentanyl related 
 
 >> MORE: Spirit Airlines pilot’s overdose raises safety questions 
 
 Brian Halye, 36, and Courtney Halye, 34, were found dead in their Centerville home March 16 by their four children who reported the deaths to police. Cocaine, opioids deadly mix 
 
 The autopsy does not make clear if the Halyes knew the cocaine they were taking contained carfentanil — a synthetic opioid 100 times stronger than fentanyl and 1,000 times more powerful than morphine. Courtney Halye had needle puncture marks on her right thigh and left wrist, the report shows, while Brian Halye had a single needle puncture mark on his right arm. Cuyahoga County Medical Examiner Dr. Thomas Gilson last week told a U.S. Senate subcommittee that he believed drug dealers may be mixing cocaine and fentanyl as a way to increase opioid addiction in the black community, according to The (Cleveland) Plain Dealer. A spokeswoman for the Montgomery County Coroner’s office tells PEOPLE that Ohio couple Brian and Courtney Halye combined the two potent substances. “It’s certainly concerning to me someone could take cocaine, or have the lack of common sense to take cocaine and fly an airplane.” 
 
 “I suspect he is not the first and will not be the last,” Nunes said.
– The reason four kids in Ohio woke up to find their parents dead: Brian and Courtney Halye not only injected cocaine, they injected cocaine laced with a tranquilizer so potent it's used on elephants and rhinos. The Montgomery County coroner has concluded that the Halyes used cocaine mixed with carfentanil, a lethal derivative of fentanyl, reports People. The coroner can't say whether the couple knew the cocaine was tainted, only that they injected a fatal dose. The story first made headlines in March not only because their four children, ages 9 to 13, found them on their bedroom floor but because Brian Halye, 36, was a pilot for Spirit Airlines who had flown just a week prior to his death. The Dayton Daily News notes that the deaths are consistent with a pattern of overdoses in which people combine opioids such as fentanyl and its derivatives with cocaine or other drugs. Carfentanil is particularly potent: 100 times more powerful than fentanyl and 1,000 times more powerful than morphine. Last month, the medical examiner in Ohio's Cuyahoga County told a Senate subcommittee that he believed drug dealers were secretly lacing cocaine with fentanyl to increase addiction in the black community, per the Cleveland Plain Dealer. It's not clear when Brian Halye had his last drug test as a pilot. (These 10 states have the biggest drug problems.)