Driscoll, Sara. F.B.I. K-9 novel.

"Diamonds are no one's best friend when the jewels in question are smuggled conflict gems. Meg Jennings and her Labrador, Hawk, have undertaken many search-and-rescue missions, but this case has an unusual twist. A Philadelphia syndicate is importing diamonds from war-torn African nations and selling them with fake certificates to Stateside dealers. Agent Finn Pierce of the Organized Crime Program is embedded with the syndicate, but being caught with a wire or tracking device would mean instant execution. If Meg, her partner Brian Foster, and their dogs can track Pierce to a deal location, they can break the smuggling chain while maintaining Pierce's cover. With the syndicate monitoring every move, it's a risky operation with more players than Meg and Brian first assumed--on both sides of the law. And when one of their own gets caught in the line of fire, the team embarks on a desperate rescue mission, knowing that mere seconds are all that separate life and death..."--publisher's description