Authorities say a series of shootings in rural Northern California left five people dead, including the shooter, and that two children were among the wounded.
An officer told ABC News the shooter, who wielded two handguns and a semi-automatic rifle, appeared to randomly pick his targets.
About 100 law enforcement officials responded to "multiple scenes, I can think of at least five scenes", after the shooting, he said. "Multiple students" have been airlifted from the scene according to Assistant Sheriff Phil Johnston, including a 6-year-old.
Brian Flint told local media his neighbor was the shooter, and that the neighbor had stolen his truck.
Separately, three people were being treated at a hospital in Redding, about 80km north of the shootings.
The Rancho Tehama Reserve - a subdivision home to about 1,485 people - is described on its website as a "quiet private country community" located 12 miles west of Interstate 5 between Red Bluff and Corning. "This guy has been insane, and he's been threatening us and everything".
The shooter is understood to have been killed by law enforcement authorities.
In addition to the four people killed in the shooting, several people were injured, including children.
The FBI has confirmed it will assist in the investigation. "I don't believe it because I wake up, take my kids, feed them cereal and put them in the truck and says 'Let's go to school like a normal day'".
The roommates lived close to the gunman, and he said that the gunman was firing off rounds.
Jeanine Quist, an administrative assistant with the Corning Union Elementary School District, said no one was killed at the school with kindergarten through fifth grades.