Police dogs die in parked vehicle Two police dogs have died in a hot vehicle parked outside the headquarters of Nottinghamshire Police
An RSPCA officer was called to the Sherwood Lodge headquarters in Arnold on Tuesday and found two German shepherd dogs dead.
An independent vet is carrying out post-mortem tests to establish how the animals died.
The Independent Police Complaints Commission (IPCC) refused to follow up a referral by police into the deaths.
Nottinghamshire's Assistant Chief Constable, Peter Davies, said: "This is a tragic incident and we value the important work our police dogs carry out on a daily basis.
"That is why we swiftly reported this incident to the RSPCA and we will be working with them very closely."
In a statement Nottinghamshire Police said the welfare of all of its animals was "of paramount importance and we endeavour to take every measure possible to ensure their well-being and safety".
The force refused to say what kind of vehicle was involved.
The Met Office said it reached 28.1C (82.5F) in Nottingham on Tuesday.
Nottinghamshire vet Andrew Wilson said: "Dehydration would have been a big factor.
"They wouldn't be able to cool themselves because panting wouldn't be effective anymore, there would be no evaporation from the tongue.
"As the core temperature rose as a result of that, and the brain temperature rose, the brain would cease to function and various other organs would fail. This happens certainly within 30 minutes."
In a statement, the IPCC said: "We received a voluntary referral from Nottinghamshire Police on Tuesday and have now considered it.
"We have decided it is appropriate for this sad incident to be returned to the police force to carry out its own local investigation.
"We understand the RSPCA has been informed and are aware the police force is working with them to investigate."
An RSPCA spokesman said: "It was reported to us yesterday by Nottinghamshire Police.
"We are investigating and they are co-operating with us.
"I am sure this isn't the first incident and it won't be the last."
Nottinghamshire Police Authority chairman John Clarke said: "This is a truly tragic incident.
"I am deeply disturbed to learn of the deaths of these police dogs, which play such a vital role in the fight against crime.
"The RSPCA has been informed and will, I am sure, carry out a thorough and speedy investigation.
"The authority has asked to be provided at the appropriate time with a full report into the circumstances.
"In the meantime we are requiring a guarantee from the force that measures are being put in place immediately to ensure that an incident like this can never happen again."
The Dogs Trust, the UK's largest dog welfare charity, said it was "saddened" by the News
In June last year Nottinghamshire Police made a public appeal for German shepherd dogs to be donated to increase the number of working dogs in the force.
Training a police dog to the standard where it can go out with an officer on patrol costs an estimated £7,000 and involves a nine-week intensive course.
The maximum sentence for causing unnecessary suffering to an animal is six months in prison and a £20,000 fine. THE BBC