OAK GROVE, Missouri (KMBC) -- An Oak Grove K-9 officer and his handler discovered what’s believed to be roughly 5 grams of pure fentanyl.

Officer Andy Anderson and his dog Merlin, a nearly 7-year-old Belgian Malinois, made the bust last Wednesday at an Oak Grove business.

The seizure was announced last week on Merlin’s Facebook page.

Anderson said Merlin is trained to detect marijuana, meth, cocaine, and heroin.

He said Merlin gave a positive hit on the substance found, but finding pure fentanyl was unexpected.

Based on Merlin’s Facebook post, the amount recovered is enough to kill about 5000 people or more than half the town of Oak Grove.

“I’ve been trying for years for the city to give him a paycheck, they won’t pay him,” Anderson quipped.

The devastation fentanyl has caused to area families is immeasurable.

Jake Hatfield, Shawn Dewey and his cousin Katie Kennedy and Gabrielle Smith Thomas all thought they were taking legal medications.

All of them were in their twenties, and each one of them died suddenly and unexpectedly of fentanyl poisoning.

Anderson said any medication not prescribed by a physician and bought through a pharmacy can pose a risk.

He said some medications might not cause a problem, but others can be laced with a fatal dose of fentanyl.

Merlin’s K-9 Unit was possible due to community donations of about $14,000.

In the five years the unit has operated, Oak Grove Police estimate Anderson and Merlin have confiscated roughly $750,000 in illegal drugs.

“He’s my best friend. I’m with him more than I am my wife and my son. It’s definitely the best police job I’ve ever had,” Anderson said about Merlin and their work together.

A man is in custody after the fentanyl bust Wednesday.

His name isn’t being publicly released because the investigation is ongoing.