DEERFIELD, Mass. (AP) — A veterinarian says two dogs left in a hot pickup truck in western Massachusetts have died.

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Erika Mueller says one of the dogs was already dead when the owner took them to the South Deerfield Emergency Veterinary Hospital on Wednesday afternoon, and the other dog died shortly after arrival.

Mueller, the hospital’s co-owner, says the well-meaning dog owner left the animals in the truck with a window open and a supply of water, but the temperatures soared into the 90s, which means it can get higher than 100 in a vehicle.

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She did not disclose the owner’s name.

Mueller says the clearest signs of heat stroke in pets include excessive panting, salivating, or lethargic behavior.

Experts say what applies for humans in extreme heat also applies for pets.

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Copyright 2012 The Associated Press.