HANFORD, Calif. (KFSN) -- On New Year's Eve, 34-year-old Salvador Valdavinos posted a photo on his Facebook page.
He's in front, pointing at the camera, surrounded by ten other men.
Two of them have since been arrested in connection to his murder that same night: 41-year-old John Reyna and 36-year-old Joe Trejo.
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Authorities say Trejo was the host of the New Year's party.
But at some point, there was an argument, during which police say Reyna shot and killed Valdavinos.
There were no 911 calls, police say, but an officer that happened to be in the area heard shots.
"He was actually somewhat nearby and he heard shots being fired, so he personally responded and asked for other units to respond," said Hanford Police Chief Parker Sever. "But it's really hard once the shots have been fired to locate where they came from, it's very difficult."
Sever says his department started getting reports that Valdavinos had not been seen or heard from.
After finding pictures from the party, police tracked down people that were there.
They arrested Trejo during a traffic stop on Friday, and on Saturday morning, they served three search warrants, including one at a Lemoore apartment complex-where they arrested Reyna.
Also on Saturday morning, detectives found Valdavinos' body, in a four-foot deep grave just outside Hanford city limits.
Police believe Trejo helped Reyna move and bury the body.
"(Detectives were) interviewing suspects, interviewing people involved, interviewing witnesses," Sever said. "During the course of those interviews, possible locations came up, and when we checked those locations we found what we believed to be a possible gravesite."
Though it started with an argument, Hanford Police are calling it a gang-related shooting, saying Valdavinos had previously been involved with one, and that the two suspects were active members of a Kings County gang.
A friend tells Action News that Valdavinos wasn't much involved in gang life anymore, but loved sports, and cared deeply about his family.
Both suspects have a long list of prior criminal charges, including several felonies in Kings County.