At least two people were killed and two others were injured Monday when a small plane crashed into a suburban Southern California neighbourhood, setting two homes ablaze, authorities said.

It wasn't immediately known whether the victims were on the ground or on board the twin-engine Cessna that went down around midday in Santee, about 20 miles (30 kilometers) northeast of downtown San Diego, Deputy Fire Chief Justin Matsushita says two people died at the scene and two are hospitalized in unknown condition.

Two homes and multiple vehicles were destroyed by fire, officials said.

Two people received burn injuries, said Fire Chief John Garlow. He didn't know their conditions or whether they were in the plane or on the ground.

One home was “well involved” by flames, and a second home also caught fire, Garlow said. A box truck, possibly a package delivery vehicle, also burned, he said.

TV news footage about an hour after the crash showed the fire extinguished and two houses and a vehicle in the street still smoldering and gutted by flames.

Jim Slaff told NBC 7 in San Diego that neighbors pulled his mother out of a window of her burning home and rescued his stepfather from the backyard. It appears their dog died.

Slaff said neighbors told him the couple was “obviously shaken up but doing OK” and taken to UC San Diego Medical Center. “It's a war zone. It's not even a house,” Slaff said after arriving at the scene.

The plane was a twin-engine Cessna C340, according to the Federal Aviation Administration. It wasn't immediately known where the flight originated or was headed, or how many people were on board.

The crash happened about three blocks from Santana High School in the city of about 50,000 residents. The school said on Twitter that “all students are secure.”