Joseph Burrola was 17 and from Rancho Cordova, California, when he was shot and killed at a crowded weekend house party on June 21, 2015. A gunman opened fire during a violent altercation; Joseph was pronounced dead at the scene and two other partygoers were hospitalized with injuries.

The Sacramento County Sheriff’s Department opened an investigation but, according to family and officials, progress has been limited by a lack of cooperation from witnesses. Despite the large crowd, crucial details about the shooter and the sequence of events remain unclear. Joseph’s family and friends held vigils to honor him and urged the community to come forward.

If anyone at the party or who has information about the shooting can help, please contact the Sacramento County Sheriff’s Department.