A shooting Tuesday morning at an elementary school in Rancho Tehama, California, left multiple victims

Authorities say a random shooting spree on Tuesday morning across Rancho Tehama Reserve, California — including outside an elementary school — killed four innocent people and wounded two children, PEOPLE confirms.

The shootings began about 8 a.m. then “evolved to multiple victims and multiple shots,” ending at a local school, Tehama County, California, Assistant Sheriff Phil Johnston said during a makeshift news conference later Tuesday.

Get push notifications with news, features and more.

No children were killed, Johnston said. There were seven crime scenes, according to authorities.

Johnston noted that the shootings were apparently unconnected and that investigators do not yet know the shooter’s motive.

“It was very clear at the onset that we had an individual that was randomly picking targets,” he said.

A domestic violence incident was reported on Monday by the gunman’s neighbors, officials said, according to the Associated Press. “There was a neighborhood dispute ongoing,” Johnston told reporters.

At least 10 people were injured,the New York Times, the Los Angles Times and the AP reported. Two students — one at the elementary school and one on their way — were among those wounded, according to the AP.

The suspected gunman was killed by law enforcement, Johnston said. Authorities believe they know his name but are still working to confirm his identity.

Image zoom The scene in Rancho Tehama Reserve, California, following a deadly shooting there on Tuesday morning Jim Schultz/The Record Searchlight/AP

Image zoom Two women embrace outside a Rancho Tehama Reserve elementary school in California, where authorities say a gunman opened fire on Tuesday. Rich Pedroncelli/AP

Rancho Tehama is about 190 miles north of San Francisco.

“We have information that he [the gunman] did several random drive-by shootings of residences” before opening fire outside the school, after which he was fleeing again before being stopped by responding officers, Johnston said.

The suspect “is known to law enforcement, but I don’t know him to be a felon,” Johnston said.

Authorities believe the gunman used a semi-automatic rifle and two handguns, which were later recovered, Johnston said.

“There was gunshots going for a good 25 minutes,” a witness at the school told local TV station KRCR.

Visibly emotional, Johnston said at one news conference on Tuesday, “It’s a very sad day for us here in Tehama County.”

Image zoom The scene at an elementary school in Rancho Tehama Reserve, California, following a shooting there on Tuesday morning. Rich Pedroncelli/AP

California Gov. Jerry Brown said in a statement that he and his wife, Anne, “are saddened to hear about today’s violence in Tehama County, which shockingly involved schoolchildren.”

“We offer our condolences to the families who lost loved ones and unite with all Californians in grief,” he continued.

A spokeswomen for the Enloe Medical Center in nearby Chico, California, initially told PEOPLE that four victims in the shooting — three children and one adult — had been transported to their facility for treatment.

As details were still emerging about the shootings, authorities also indicated that a “number” of students were hospitalized.