Dover police K-9 Grinko in his cruiser crate. The retired member of the force died Thursday, April 18, 2019.

DOVER — Members of the Dover Police Department are mourning the loss of a beloved patrol dog who helped apprehend large-scale narcotics dealers during the course of his career.

Grinko, a German shepherd, died of natural causes Thursday. He was 10 years old.

Grinko served as detective Timothy Keefe’s partner from 2010 until 2017, when Grinko retired. Keefe and Grinko had a special bond which lasted until the day he died.

“He really loved police work and he loved his job. He was a good partner. He covered my back more times than I can remember,” Keefe said Friday afternoon.

Grinko was certified as a patrol dog through the United States Police Canine Association and was also a member of the Strafford County Regional Tactical Operations Unit where he served as a tactical K-9. Toward the end of his career, Grinko and Keefe were assigned to the DEA Tactical Diversion Squad where Grinko helped the team by locating and apprehending large-scale narcotics dealers, according to a news release.

“He was effective when we had him here at keeping most of the suspects we were looking for confined. They weren’t going to think about running,” Keefe said.

In Dover, Grinko tracked down a man who robbed Smiley’s on Main Street with a sawed-off shotgun. He helped stop a series of burglaries from houses near the high school, Keefe said.

Grinko also helped find missing people. He tracked down a suicidal man who was found face down on a set of railroad tracks in Rollinsford.

One day, without prompting, Grinko found a woman who was face down in the water near Hilton Park at Dover Point, Keefe said.

Keefe cared for Grinko after Grinko’s retirement but said even then the dog was always on patrol.

“He never had it in his brain that he could relax. I’d be doing laundry and he’d be looking down the hall,” Keefe said.

Grinko, who was born Gringo vom Morfelder Land on Oct. 23, 2008, in Germany, has a sister named Gypsy, who is a K-9 at the Barrington Police Department.