A woman in Pennsylvania was killed Wednesday morning after she ran out of her burning house -- then ran back in to try saving her pets.

Two people and one dog in the Bensalem home made it to safety. It was unclear how many pets died in the home along with the woman, believed to be in her 40s. When crews went inside they found her body on the first floor.

The single-family home was fully engulfed in flames at 6:30 a.m. but was declared under control before 7 a.m., Battalion Chief Rob Sponheimer told Fox 29. The cause was unclear.

Firefighters say the fire spread quickly in the wood-framed house, and an oxygen tank may have exploded early on. As many as 60 firefighters drilled holes to ventilate the home but encountered trouble with the plywood above the ceiling and upstairs storage.

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Firefighters on the scene of the fire at a Bensalem home that killed a pet owner trying to rescue her animals. (Fox)

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Sponheimer warned, “Once you’re out, stay out,” and to let authorities know about the fire.

Paramedics rushed the survivors to the hospital for possible smoke inhalation and burns. A firefighter was also reported to have suffered minor injuries.

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Bensalem home engulfed by flames. (SKYFOX)

Cars in the driveway were destroyed along with the home. It is unclear whether or not there were smoke detectors in the house about 40 minutes northeast of Philadelphia.

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