Officer Ronil had been employed with the Newman Police Department since 2011.
The suspect had fled the scene in his vehicle prior to assisting officer's arrival.
"The vehicle does not have an actual California license plate", said Stanislaus County Sheriff Deputy Royjinder Singh (who is not related to Ronil Singh).
The 33-year-old officer was rushed to a hospital and died from gunshot wounds.
Authorities say they have located the pickup truck that they believe the man who fatally shot a California police officer was driving.
The Stanislaus County Sheriff Department is leading the investigation into Singh's murder.
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TV camera crews had gathered outside the Tokyo jail on Friday morning in hopes of catching sight of Ghosn being released. Greg Kelly, a former Nissan director accused of helping Ghosn under-report his income, was also indicted last week.
A 33-year-old Indian-origin police officer in the USA state of California has been killed after being shot by an "armed" unidentified gunman while he was conducting a traffic stop.
The public was asked for information about his identity and the California Highway Patrol warned that he was considered armed and risky.
Ground and air units were searching for the suspect based on surveillance photos taken at a convenience store shortly before the attack in Newman, about 100 miles (160 kilometres) southeast of San Francisco. He was a native of Fiji, the Stanislaus County Sheriff's Department noted. Jerry Brown's office. Before joining the Newman department, he served the Merced County Sheriff's Department. He is survived by a wife and an infant son.
33-year-old Ronil Singh had made a traffic stop in Newman.
Flags will be flown at half-staff at the Capitol building in Sacramento, Brown said in offering condolences.
This undated photo provided by the Newman Police Department shows officer Ronil Singh of Newman Police Department who was killed by an unidentified suspect.