A shooting was reported at 1:30 a.m. at a home in the 44500 block of North Tabler Avenue, according to the Los Angeles County Sheriff's Department.
Firefighters were dispatched to the one-story home at 1:43 a.m. and extinguished the fire by 2:30 a.m., according to a Los Angeles County Fire Department dispatcher.
Officials said that paramedics rushed one person to a hospital. The extent of that person's injuries was unknown, and it was unclear if the individual was a victim or a suspect.
Investigators said a fifth person, a 16-year-old girl, was also home at the time of the incident but wasn't hurt. She called 911 and hid in her bedroom.
"The family member we have at the station heard the gunshots around 1:27 this morning... she stayed in her room because she was scared, and that's when deputies were able to locate her and extract her," said LASD Lt. Steve Dejong.
Deputies were able to rescue the girl from the burning home.
"They were able to pull three individuals out of the home, out of the residence. L.A. County Fire showed up immediately thereafter and extinguished the fire and were able to pull two more individuals out of the home," Dejong said.
Three people were pronounced dead at the scene. Investigators said the two men and one woman killed were all in their early 20s, and may have been in bed when the shooting took place. Their names have not been released.
The grisly scene left neighbors in shock.
"It's a real quiet area so this is really shocking to us. We can't wrap our minds around it because it's insane, it's insane!" said Hector Gonzalez, a neighbor.
The Los Angeles County Sheriff's Department said there were more people living at the house who weren't home at the time of the incident. They're being interviewed by investigators who have not ruled out that one of the four people shot could also be the suspect.
A motive for the shooting and fire remains under investigation.
Anyone with information regarding the shooting was urged to call the sheriff's Homicide Bureau at 323-890-5500. Callers who wish to remain anonymous may call Crime Stoppers at 800-222-8477 or visit lacrimestoppers.org.