A police K-9 in Mississippi left in a patrol car died when the vehicle malfunctioned and shut off its air conditioner on a hot day, department officials said.

The dog, an 8-year-old German shepherd named Thor, was in a patrol unit outside of the Vicksburg Police Department on Tuesday when the vehicle “apparently malfunctioned” and its engine turned off, Police Chief Milton Moore said in a statement.

The dog was rushed to a vet for treatment, but died early Wednesday from complications of being left inside the vehicle for less than 30 minutes. Moore told the Vicksburg Post that it’s normal procedure for a police dog to be kept inside a patrol unit with its motor and air conditioning running for hours at a time.

“We don’t know what happened to force the vehicle to shut down,” Moore told the newspaper. “The vehicle is in the shop right now to find out what could have happened.”

Thor, who joined the department in 2012, is credited with more than 60 felony arrests and apprehensions, including many drug-related busts, police said.

Tuesday’s high temperature in Vicksburg was 95 degrees.

Thor was found inside the vehicle by his handler, Officer Donnie Heggins, who kept the animal at his home with his family, Moore said.

“He’s one of us,” the chief told the newspaper. “He might be an animal, but he was an officer … But we are also praying for the Heggins family. He was a part of their family. It was shocking to know how hurt they are by this loss.”