RED BLUFF, California - Six people are dead, including a suspected shooter, and multiple students are being treated after shootings at several scenes in rural northern California including an elementary school, according to a Tehama County sheriff's official.

Jeanine Quist, an administrative assistant with the Corning Union Elementary School District, says no one was killed at the Rancho Tehama Elementary School Monday morning but a "number" of students were shot and wounded. At least three children and one adult were transported to Enloe Medical Center, in Chico, California, the hospital confirmed to KHSL. Three people were transported by ground and one by helicopter. 

Tehama County Assistant Sheriff Phil Johnston, who according to CBS affiliate KHSL addressed reporters near one of the scenes, said deputies were first alerted to a shooting in Rancho Tehama Reserve at around 8 a.m.

"That evolved to multiple victims and multiple shots at the school," Johnston said, adding that he's been told the suspected shooter was shot and killed by law enforcement. Investigators recovered a semi-automatic rifle and two handguns, according to Johnston.

About 100 law enforcement personnel are currently working at least seven crime scenes in the area, he said.  

"I know that we have Medivaced a number of students," Johnston said, referring to the use of helicopters for the emergency transport of victims to hospitals. Johnston said the school had been cleared by 10 a.m. but he did not have any information about the victims there.

All other students have been brought to a safe location, he said.  

"It's a really sad day for us in Tehama County, really," Johnston said, choking up as he finished addressing reporters.

Brian Flint told the Record Searchlight newspaper in the city of Redding on Tuesday that his roommate is among the victims and that his neighbor was the gunman. He said his neighbor, whom he knows only as Kevin, also stole his truck. 

He said he and his roommate told authorities that their neighbor was acting "crazy" and threatening them.  

Flint said the neighbor had been shooting "hundreds of rounds" from large magazines. 

The community is located about 130 miles north of Sacramento. The FBI confirmed to CBS News they are sending agents from Sacramento, Redding, and Chico to assist with the investigation.

California Gov. Jerry Brown issued a statement about the shootings late Tuesday morning.

"Anne and I are saddened to hear about today's violence in Tehama County, which shockingly involved schoolchildren," Brown said. "We offer our condolences to the families who lost loved ones and unite with all Californians in grief."

On Wednesday, the Tehama County assistant sheriff said wife of gunman who went on Northern California rampage found dead in home, bringing toll to 6.

© 2017 CBS Interactive Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.