Authorities are investigating after the decomposed remains of up to three dogs were found inside a car parked in downtown San Antonio.

Animal Care Services and the San Antonio Police Department responded Monday to a report of a strong odor coming from a vehicle parked in the 100 block of W. Nueva Street, near the Bexar County Justice Center, according to an ACS news release.

Officers discovered the heavily decomposed remains of what are believed to be up to three dogs inside the vehicle.

Authorities believe the animals may have died from exposure. A veterinary examination and necropsy will determine the exact number of animals, confirm their identities and establish the cause of death.

ACS and SAPD are using evidence recovered from the vehicle to identify a suspect.

The suspect could face fines and animal cruelty charges, according to ACS. City code prohibits leaving an animal unattended in a vehicle in a way that endangers its safety.

“Residents should never leave an animal unattended inside a vehicle,” ACS said. “Anyone who sees an animal confined in a vehicle that appears to be in danger should immediately report it to law enforcement.”

The temperature inside a parked vehicle can rise by 20 degrees in just 10 minutes, even if a window is cracked, according to the Texas Department of State Health Services.

Because pets cannot regulate their body temperature as effectively as humans, they are especially vulnerable to heat-related illness.