Before a former school officer in Georgia allegedly left a police dog in a hot patrol car this month resulting in the animal’s death, he may have shot and killed another police dog in 2012, the Cherokee County Marshal’s Office said Wednesday.

Daniel Peabody, 50, who was arrested this week in connection with both deaths, resigned last week from his position as a lieutenant with the Cherokee schools police.

The resignation came just days after a dog named Inca died from heat stroke on June 10. Peabody said he forgot about Inca, a 4-year-old Belgian Malinois, when he went into his house about 4:15 p.m., Cherokee Chief Marshal Ron Hunton said.

It was the investigation into Inca’s death that produced evidence suggesting Peabody shot and killed the other dog, Cherokee marshal’s officials said Wednesday.

That dog, a yellow Lab named Dale, was assigned to Peabody from 2007 to 2012 when he lived in Paulding County, WSOC TV reports.

Investigators and forensic veterinarians are trying to determine exactly what happened to Dale, including exhuming the dog from his burial site at Peabody’s former home.