The shots rang out just before 5 p.m. Saturday. Norm Trevena was outside feeding his horses when he heard the gunfire.
"About four, five, then I heard five more a few minutes after that," he said.
Trevena said suddenly, a man on a tractor holding a gun drove out of the open fields.
"And then he just drove by, and then he hit my neighbor's, went by my neighbors because I told my neighbor, 'Hey I'm going to go see what's going,' on and he pointed the gun at him," Trevena said.
Trevena and his neighbor called 911 immediately, not knowing they had just come face to face with a suspected murderer.
Simi Valley police believe the suspect killed his mother just moments before inside her home on the 1100 block of Mellow Lane.
"The Simi Valley Police Department received a phone call from an individual who identified himself as the brother of a subject. He explained to us that his brother had called him and told him that he had shot his mother," said Simi Valley Police Department Cmdr. Stephanie Shannon.
When officers arrived at the home, it was on fire, and the mother was found dead inside.
Officers from the special operations unit responding to Trevena's and other residents' calls of an active shooter came across the armed suspect riding his tractor a few blocks away.
"We heard about five more shots, and then after that there was another 10 shots on and off and it sounded like it was handguns and rifles," said witness Rob Lawson.
"When they come into contact with an individual with a firearm those officers have to make quick decisions," said Shannon. "That decision, in this case, resulted in an individual being shot by our officers, and what I would suggest, has been the direct result of saving people's lives."
Trevena and his neighbors couldn't agree more.
"He could have shot my neighbor down the street, he's the first guy that saw him, and then he could have shot me, and then he could have shot my neighbor right next door to me," he said.
So far officials do not have a motive, but they do say they have had recent calls about the suspect dealing with mental health issues.