The body of 23-year-old Felipe Bravo Junior was found in the trunk of his car in Monterey County on New Year's Day. Bravo lived in Los Banos and attended classes at the campus there.
Authorities took one suspect into custody in March, but he was set free because the district attorney's office didn't have enough evidence to charge him.
The bravo family originally set up a reward of $10,000 for information in finding the killer or killers. Tuesday they raised the reward to $25,000.
"Somebody in this town knows what happened that night, and somebody in this town needs to come forward and tell us what happened and provide our family with some comfort of what happened to my brother that night," said Flor Bravo, Felipe's sister.
"We're taking any kind of lead we can get, we would like it if anybody has any more information that we don't have to come forward. Obviously to strengthen the case and get us a good prosecution and conviction out of it," said Tom Mackenzie with the Merced County Sheriff's Department.
Both the Bravo family and the sheriff's department are asking for the public's help in solving this case. If you have any information you are urged to contact the Merced County Sheriff's Department.