Firefighters had to rip the front door off the East Lanza Court residence to gain entry, witnesses said.
What appeared to be the smell of ammonia prompted a call for a hazardous materials unit, they added.
A "large number" of pets, several of them dead and some barely alive, were found, along with numerous cages, trash, litter and debris, responders said.
Police cordoned off the area around the house with crime-scene tape.
However, there appears to be "nothing suspicious at this time," said Police Capt. John A. Zotollo, Jr., the officer in charge of the department.
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