SAN JOSE — Nearly 100 cats perished early Tuesday morning in a house fire where fencing the homeowner installed to pen the animals briefly trapped her in the burning home before firefighters cut her out and rescued her, the San Jose Fire Department said.

According to fire Capt. Reggie Williams, the resident, a woman in her 70s, made her South San Jose home into a cat sanctuary. She served as a volunteer rescuer, caring for and neutering the animals for adoption or, failing that, eventual release.

“There were cats in every room of the house,” Williams said.

The homeowner in the 6900 block of Polvadero Drive, near Bernal Avenue and Santa Teresa Boulevard, called 911 at 1:43 a.m. after the lone dog that lived with her woke her up, and she saw fire and smoke coming from a bedroom.

“She had a smoke detector, but for some reason it didn’t work. The dog alerted her,” Williams said.

A fire dispatcher instructed her to get out of the home, and she exited through a rear door, but was trapped in a patio she had enclosed with a metal netting to keep her rescue cats from escaping.

She was ordered to stay low. Firefighters found her in a fetal position with smoke and fire wafting above her. Crews used axes to cut through the fencing and pulled her to safety.

“The dispatchers kept her calm, told her to stay low and told us where she was. We went directly to her,” Williams said.

It took about an hour for firefighters to put out the flames. Afterward, they removed the bodies of nearly 100 cats, most of whom Williams said died from smoke inhalation rather than direct contact with the fire.

Neither the resident nor any of the two-dozen fire personnel were injured. Her dog also escaped.

A half dozen cats that survived the fire were handed over to the custody of the city’s animal services department.

Williams said a cause of the fire is under investigation but that it does not appear suspicious.

Some expressed concern about the sheer number of cats being housed at the location and the resident’s ability to care for them. San Jose animal services visited the home last year after the resident applied for status as a rescue organization, and while she was denied, the agency also did not find anything amiss with the animals’ conditions.

“A veterinarian was provided access to the house and did not find any serious medical conditions or anything that would be at a criminal level,” Capt. Jay Terrado said. “The house was nice and clean. The only violation we had was being over the limit.”

Terrado was referring to the five-cat limit for city households. While he acknowledged she was clearly in violation of that, the most the agency could do was impose a modest fine because the home was otherwise in order.

Contact Robert Salonga at 408-920-5002. Follow him at Twitter.com/robertsalonga.