The flames were big at the home on Ensalmo Avenue near Hillsdale Avenue. Firefighters say a fire at 11 p.m. is a high risk.
Often times people are sleeping, unaware of the life-threatening danger.
911 callers said people were trapped inside, but by the time firefighters arrived, a man and his teenage daughter had already escaped while his parents, an elderly couple, were rescued by some Good Samaritans.
3 alarm fire on Ensalmo & Hillsdale in San Jose destroys home. 4 adults escaped uninjured.— Matt Keller (@MattKellerABC7) October 19, 2016
Video from Ryan Nelson. pic.twitter.com/9L5VwvEnap
"There were some elderly people in the back of the house. They pulled them out and threw them over the fence and brought them out to the street," neighbor Ryan Nelson said.
Explosions rocked the neighborhood. Several people said they were so strong, the shook their homes.
Firefighters called for three alarms and it took 80 minutes to knock down the flames.
Will Gemo recorded video of it on his phone. "I ran down here and got a video of the fire. It was a crazy fire, explosions going off. And we were just praying that it wouldn't spread and luckily it didn't," he said.
Firefighters believe the explosions may have been the tires on two vehicles popping from the heat.
The son and his elderly parents came back to the home Wednesday morning. He wouldn't go on camera but told ABC7 News that he started it and it was accidental.
Several neighbors say police have been out here before and a lot of suspicious people go in and out of the home at all hours of the day.
"The police have been out twice. They had the streets blocked off and everything one time," neighbor Ed Schneickert said.
Firefighters said a fire cause investigator was going to be out Wednesday morning but one has yet to arrive.
As for the family, they said they have insurance and are currently being taken care of by the Red Cross.