Police say they responded to a call around 5:15 p.m. in the 43000 block of Lindenwood. When officers arrived, they found the body of a man who was pronounced dead at the scene.
The shooting allegedly took place after an incident between two neighbors.
Fremont Police say they believe they have the person responsible in custody.
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Neighbor Yue You told ABC7 News he had just driven home and pulled into his driveway, when suddenly the victim ran up to his car and started banging on his window and threatening him - totally unprovoked.
You said he feared for his life and started quickly driving away, calling 9-1-1.
After he drove off, the victim then allegedly went back to the driveway, where You's elderly stepfather had been.
At that point, there was allegedly some type of confrontation with the victim again threatening the elderly man, who repeatedly warned him to step back or he would shoot him.
At some point, a shooting occurred.
You says the move was in self-defense.
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He explained the situation to ABC7 News, "He like repeats, 'I'm going to kill you, I'm going to bury you to the ground and all that, you know. I don't even do nothing. I don't even know him. Like I never met him before."
The victim's second cousin, Karthik Manivannan, also spoke to ABC7 News this evening.
He says he believes his cousin was having some sort of psychotic episode over the past four days or so.
He says he was never threatening to anyone, but would ramble on incoherently and then leave the house for walks, come back and be seemingly fine.
Manivannan says they called police twice but were told that the victim didn't qualify as a threat because he was not aggressive.
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"We tried our best to get him mental help," Manivannan said. "The system and the cops kept telling us that 'the best we could do is wait.'"
Now, Fremont Police say they are still in the early stages of their investigation into this incident, and that more details will come out in the coming time.