FRESNO, Calif. (KFSN) -- Hanford Police say they need to speak with 37-year-old Mark Valdivia and need the public's help finding him.
They say he may have seen 34-year-old Salvador Valdavinos murdered on New Year's Eve, and think he could have information that helps them understand what happened that night.
"Our goal is to interview, speak to, and talk to everybody that knows anything about this case," said Hanford Police Captain Karl Anderson. "The people that we are asking people to help us find are people that we still need to talk to."
Investigators were able to use photos from a New Year's Eve party to track down the primary suspects in the murder of Valdavinos-including John Reyna, the alleged shooter, and Joe Trejo, the host of the New Year's party who's accused of helping Reyna move and bury the body.
But last week, detectives arrested another person in connection to the case-58-year-old Pete Reyna.
The Kings County District Attorney's Office charged him with accessory after the fact.
The complaint alleges he brought bleach and Pine-Sol to Trejo's home after witnessing the murder.
RELATED: Hanford Police used photos from New Year's Eve party to track down murder suspects
Valdavinos' body was found in a four-foot grave just outside the city a few days after he disappeared.
Police say people at the party haven't been cooperative with detectives, as is common with gang-related crimes.
"Simple questions are met with I don't remember, I don't know," Anderson said. "So it takes a lot of time, a lot of effort."
But police say they've already received many tips from the public in the case, and they're hoping they'll do so again by helping them find Valdivia.
Court documents also show that prosecutors will seek the death penalty for the alleged shooter, John Reyna.
Reyna and Trejo have a preliminary hearing on June 25th.
Hanford Police make third arrest in connection to NYE murder, still want to talk to another person
Kings County deputies arrest man yelling at government center staff about COVID-19, acting 'bizarrely'