No children were among those killed in the attack, which only ended when law enforcement officers, responding to the carnage, fatally shot the gunman. He says he and his roommate told police that their neighbour was acting "crazy" and threatening them.
Johnston said the gunman, apparently frustrated, left the school grounds and resumed his random shooting before crashing the vehicle.
It was "very clear" early on that "we had a subject that was randomly picking targets", he said.
He said the suspect has been identified, but his name has not been released pending notification of next-of-kin.
The shooting broke out at a home in Tehama County, in Northern California and continued at the school, local authorities were quoted as saying. He said investigators were still trying to confirm the identity of the killer, who he said was armed with a semiautomatic rifle and two handguns. Mercy Dignity Health confirmed that the hospital has received three patients.
Magnitude 5.5 quake jolts South Korea
The Pohang natural disaster is the strongest Korea has experienced since 2016, after the magnitude 5.8 quake in Gyeongju. South Korea has relatively little seismic activity, compared with Japan to the east.
The shooter was killed by law enforcement.
The nearby Rancho Tehama Airport was placed on lockdown. A woman and another child were shot in a truck that was driving near the school and taken to the hospital, he added.
Rancho Tehama is a community of about 3,500 northwest of Corning.
Gov. Jerry brown issued a statement on the shooting, saying: "Anne and I are saddened to hear about today's violence in Tehama County, which shockingly involved schoolchildren".
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