Authorities in Mercer County said a county K-9 unit died Wednesday after his handler left him in a patrol car, prompting the sheriff to suspend the program during the investigation.

Mercer County Sheriff Jeff Grey said Deputy Chad Fortkamp left his K-9 unit, Zak, in his patrol car while he completed the reconstruction of a traffic crash at the office around 1:00 p.m.

“When at the office, the car is either left running with air conditioning on or Zak comes into the building,” said Grey. “The car was not running and it appears that Zak was overcome by the heat.”

After an autopsy, Zak, who suffered from a pre-existing heart condition, is believed to have died after being aggravated by the temperature of the car. The K-9 Unit’s Veterinarian stated that even a perfectly healthy dog may have not survived the heat.

A thorough investigation into why the dog was in the car and why the car did not have the air conditioning running will be completed, said Grey.

The results of the investigation will be released upon its completion when a decision for disciplinary action against Fortkamp will be determined.

“I am deeply disappointed and apologize to the members of the Moose Lodge, the Eagles of Celina and others who helped fund the K-9 program,” said Grey.

In 2010 the Moose Lodge donated $5,000 to the program in addition to the $1,500 from the Eagles of Celina for the purchase of Zak.

The Sheriff’s Office plans to suspend the K-9 program until further notice after losing two dogs within the last three years.