Fentanyl is the fifth odor the K-9s are trained to detect, joining methamphetamine, heroin, cocaine and marijuana.

The victim and Jones exchanged texts as she sought marijuana, police said. Court documents show he also offered a Percocet pill that turned out to be fentanyl.

West Des Moines man arrested after Des Moines police seize fentanyl, pills and cash

A man was sentenced to prison after he mailed oxycodone pills containing fentanyl to a Utah woman, who died after ingesting the narcotic.Bryan Waltter McMahan,