Burguan said the shooter, Cedric Anderson, 53, of Riverside, entered the classroom with a large caliber revolver and opened fire "without saying anything", killing Karen Elaine Smith, also 53, also of Riverside.
Burguan said, at the time of the shooting, there were 15 students from grades one through four in the special needs classroom, along with two adult aides.
From the front desk, he walked to his wife's classroom where he opened fire.
Police identified the boy who died as Jonathan Martinez.
The students were wounded because they were near the teacher when the shooting started, officials said.
- After two people were killed in a shooting at a classroom in a San Bernardino elementary school on Monday, the city's bishop is praying for the victims and the school community.
Maria Garcia says the shooting is believed to have stemmed from a domestic dispute.
The two students were struck by gunfire had been standing behind Smith, he said.
G7 leaders to push Russian Federation to stop backing Syria's Assad
The U.S. military action has renewed the world's focus on Assad's fate and on Syria's civil war, now in its seventh year. "I think the president has authorization to use force", he said.
McIlroy rues cruel ricochet that leaves him five back
I had a great chance on 11 and 14, and from where I hit my drives on 13 and 15, I should be making birdie off the tee shots. There was better news for Brandt Snedeker as he shot 69 to move to two over par for the tournament.
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However, Lee Hodson is fit again and likely to come back into the side. But football is the moment and Rangers are Rangers.
Authorities said the shooter had an existing relationship with a North Park teacher who was a victim, but they have not provided details about the adults' relationship. The school will be closed for at least two days while the investigation continues, San Bernardino City Schools Superintendent Dale Marsden said. For all elementary and middle schools, a Campus Support Police Officer is assigned to the area for a quick response to an emergency, she said. She called Monday's shootings "every parent's worst nightmare". They were reunited with their parents hours later.
Frantic parents rushed to North Park Elementary after the shooting. Their conditions were not immediately known, police said.
"While no educational institution or campus can ever be 100 percent safe from an intruder or other safety threat, maintaining vigilant Planning, Preparedness, Response and Recovery protocols can help prevent and mitigate tragedies", Zipperman said in the statement.
The woman said she could see her daughter on the other side of the fence and said she was "crying" as she held hands with her classmates.
When students got to the high school, many carrying glow sticks they had been given to pass the time, they got hugs from emotional parents, many in tears. "It was a typical morning and then chaos broke out".
Students gather before being taken on buses to Cal State. In December 2015, Syed Rizwan Farook and Tashfeen Malik killed 14 people during a Christmas party at a county health department building.
Law enforcement secure the scene of a mass shooting in San Bernardino, CA., on Monday. It was hit hard by the great recession, seeing rises in unemployment and violent crime.