Dramatic video was caught on camera by neighbors as flames tore through a 200-year-old house in Lancaster.
"As soon as you opened the door, you could feel the heat coming from the fire," said Josh Zimmer, who lives directly across the street.
For a time, Zimmer's family was concerned the fire would spread.
"We were at one point trying to pack up some of our valuables," he said.
The house went up in a matter of minutes after 11 p.m. Saturday.
Luckily, no one was home. But the owner's daughter was able to alert firefighters that there were a dozen oxygen tanks inside.
It was just in time. Firefighters chose not to go in.
"At that point, with the fire so far advanced, we chose not to go in, and minutes later, pretty much all 12 exploded," said Lancaster Fire Chief Mike Hanson.
The owner of the home, who neighbors say is in his 70s, was away.
"At least Gordon wasn't here," said a friend, Barbara Wood. "That is kind of a blessing."
Two dogs were inside. Firefighters had to rescue them, giving one oxygen.
"We got one out initially, and then a few minutes later, they went back in and made two other attempts to find it," said Hanson. "They did find it and were able to resuscitate it.
Firefighters were busy putting out hot spots all afternoon.
The cause of the fire is still under investigation.