Missouri police dog dies in hot patrol car after air conditioner malfunctions

The Arnold Police Department said 4-year-old Vader, passed away from heat exhaustion on Wednesday. (Arnold MO Police Department)

A police K-9 has died in Missouri after the air conditioner in his handler's patrol car stopped working while the police dog was left inside on a hot day, authorities said.

The Arnold Police Department said 4-year-old Vader, passed away from heat exhaustion on Wednesday.  The town, a suburb of St. Louis, had high temperatures in the mid-90s.

"The K-9 handler left Vader in a running, air-conditioned patrol vehicle, which is necessary and common practice when the K-9 partner is not actively engaged in police work," the police department said. 

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When Vader’s police handler returned to the vehicle, it was discovered that the air conditioning system malfunctioned, authorities noted.

Vader was immediately transported to a local veterinarian clinic where he showed signs of improvement. He was then transported to a 24-hour clinic for further treatment. 

"Unfortunately, we learned (Wednesday) night that there were no further treatments available for Vader, and he succumbed to his injuries," police said.

Arnold police said all department K-9 vehicles come with a system that will alert the handler by phone, turn on the emergency lights and siren, honk the vehicle horn, activate cooling fans and roll down the windows if the vehicle gets too hot.

"In this instance, the heat alarm system failed to activate," the department said in a release to FOX Weather.

The Arnold Police Department said they are investigating to determine what went wrong.

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