More than 1,000 people including hundreds of fellow police officers from adjacent states—turned out at a funeral in rural Kentucky late last week to pay their respects to Jason Ellis, a 33-year-old K-9 officer mowed down in what authorities believe was an ambush.

Fido, Ellis' police dog, was there, too, placing his paw on the closed casket—a moment captured in a devastating image by photographer Jonathan Palmer.