A former employee of two northwest Missouri ambulance services has admitted to replacing pain-killing drugs with sterile water.

The Associated Press and KSHB in Kansas City reports that federal prosecutors say 31-year old Joseph Comstock, of Bethany, MO, pleaded guilty on Tuesday (Sept 12), to tampering with a consumer product.

The crimes allegedly occurred while he worked for the NTA Ambulance District in Bethany and the Community Ambulance District of Daviess County, in Gallatin.

Prosecutors say Comstock emptied vials of morphine and fentanyl for his personal use and replaced them with sterile water, in ambulances.

A press release from the Western District of Missouri - U.S. Attorney's Office, federal officials were notified in March 2015, of possible drug tampering at the NTA Ambulance District in Bethany. The chief of EMS reported that an employee had noticed two morphine syringes had broken tamper-evident seals.

The press release also says on January 30, 2015, an employee noticed that two morphine syringes had broken tamper-evident seals. On February 27, 2015, ambulance employees looked through narcotic boxes kept on the three NTA ambulances. They found a number of drugs were missing tamper-evidence caps and had broken tamper-evident seals, including midazolam, lorazepam, morphine, and fentanyl.

Federal agents then installed surveillance equipment at the Bethany NTA building on March 18, 2015. A camera was also placed on an ambulance, which was taken out of service, according to the report.

Comstock was recorded on the surveillance video as he stole morphine from the ambulance on two separate occasions in March 2015. Comstock later admitted that he had tampered with drugs on all the ambulances prior to that as well.

Comstock also admitted that he tampered with drugs when he visited the Gallatin, MO ambulance building in February 2015.

According to the reports, Comstock told prosecutors he started tampering with drugs in 2014. He also admitted that on at least two occasions, he treated two trauma patients with hip fractures with watered-down Fentanyl.

Under federal statutes, Comstock could face a sentence of up to 10 years in federal prison without parole, on each of the 3 counts.

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