Fresno Police Chief Jerry Dyer says 42-year-old Lawrence Jones clocked in for work at the Valley Protein Plant just before five Tuesday morning.
His co-workers say, he worked for a little while and then left.
When he came back, he was on a mission to kill.
"He walked up to one of the victims, who was identified as Salvador Diaz. He placed the 357 caliber handgun to the side of the head of the victim, pulled the trigger one time. One round struck him in the head and he fell on the floor," Dyer said.
Chief Dyer says 42-year-old Lawrence Jones then went on to cherry pick his other victims.
"What we believe at this point is he walked up to Diaz, shot him, immediately walked over to the second victim, shot him, walked over to the third victim, shot him; again, none of those victims knew that a round had been fired at that point."
That's because many at the plant wear earplugs to drown out the loud noise.
After police say Jones shot his 3rd victim, another co-worker saw what was going on and ran.
Police say Jones shot her before she could get away.
He then walked over to yet another co-worker, put a gun to his head and pulled the trigger. But by this time, the gun was out of bullets.
"What it does appear is that he was very selective in who he shot. He had the opportunity to shoot other co-workers that were in the business at that time but chose not to. In fact, (he) walked around them to get very close to the intended targets, place the gun against their person or very close and fire each of the rounds," Dyer said.
In all, police say, Jones shot four people.
32-year-old Salvador Diaz was shot in the head and died at the scene.
34-year-old Manuel Verdin, was also shot in the head. He died at the hospital.
28-year-old Arnulfo Conrriquez was shot in the neck and is listed in critical condition.
32-year-old Fatima Lopez was shot in the backside. She's already been released from the hospital.
After the shooting, police say, Jones, a discharged parolee whose rap sheet dates back to the 90's and includes burglary, robbery and auto theft, left the business, walked down the street, reloaded his gun and shot himself in the head.
He was pronounced dead at the hospital.
"We've had incidents in Fresno where we've had multiple people shot and killed. We've had several of those unfortunately over the years. But in terms of it being specific to the workplace, where as today we had workplace violence and co-workers being shot and killed, we have not seen that in Fresno," Dyer said.
Fresno County Coroner David Hadden says there is an autopsy planned for Jones Wednesday at 11:30 a.m.
Hadden says they'll look closely at the toxicology report to help them figure out how and why this all happened.