One person has died after neighbors reported hearing loud "booms" before a house caught fire in Penn Hills on Tuesday afternoon. 

The Penn Hills Fire Marshal confirmed to KDKA-TV that an 84-year-old woman died in the fire as she was unable to get out. 

Neighbors said they heard two large "booms" before the fire broke out on College Street, Penn Hills fire investigator Chuck Miller confirmed.

Crews are trying to find someone inside one of the homes, Miller said. He also said that crews are up against hoarding conditions. 

"It's really upsetting to see that," said Frank Buczkowski, a neighbor said. 

Buczkowski captured the flames and smoke billowing from his neighbors' home on College Street. 

"I went into the alley and I saw a lot of smoke and a lawn on fire, and then the house was on fire and smoke was pouring out," he recalled.   

A man who lived next door told KDKA-TV she was his second cousin and that she grew up in the home. She lived there with her brother and Miller said one of them was unaccounted for when the fire crews got on the scene. 

Miller said they faced hoarding conditions once inside the home. 

Several neighbors said they felt two loud booms and it woke up Brandon Revino-Bennett, who ran outside to see what was going on. 

"I was asleep on my couch and when the first bang went off, I woke up," he said. "The second one, I ran outside and I just saw the house engulfed in flames. It was just coming out of the foundation, it wasn't up top yet. It was just coming up from the bottom of the house." 

The house is a total loss and the house next door suffered heat damage.

According to the fire marshal, the cause of the fire was a propane leak in the basement that ignited two kerosene heaters to explode. 

The victim was found under debris in the basement and they believe she collapsed on the first floor and then fell into the basement when the kitchen floor collapsed.