The sheriff's office responded to a call of an injured person just before 1:30 am on Fowler Avenue between Olive and Clinton.
When deputies arrived, they found a woman with serious injuries inside of a car.
First responders tried to save her, but she died at the scene.
"There are some suspicious circumstances that's why we're treating it as a homicide right now," said Fresno County Sheriff's Lt. Joe Smith.
The busy road was closed for hours as detectives were on scene, canvassing the area for evidence until the sun came up.
At this time, it is unclear what led to this mysterious death or who may be responsible.
The women's identity has yet to be released.
Anyone with any information is being asked to contact the Fresno County Sheriff's Office.
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