Alonzo was last seen in Oakland, California on November 20, 2004. She has never been heard from again. Her family reported her as a missing person after she did not attend their Thanksgiving celebration on November 24. She had previously told them she planned to attend.

In early December, Alonzo's family members asked her boyfriend of two years, Eric Mora, if he knew her whereabouts. He told them he had dropped her off at a liquor store on November 20 and had not seen her since then. He appeared unconcerned about her disappearance and said she would probably return home soon. However, Alonzo's relatives believed foul play was involved in her case and suspected Mora had harmed her. Mora and Alonzo's relationship had been troubled prior to her disappearance. He admitted to Alonzo's daughter that they were constantly arguing, and she advised him to end the relationship.

Mora had mulitiple scratches on his hands after Alonzo's disappearance. Her blood was found in his brother's house in the 6200 block of Brookside Drive in Oakland. There was evidence that someone had tried to clean it up, and two rugs were missing. Mora was charged with Alonzo's murder in February 2007. Authorities believe he beat, shot or stabbed Alonzo to death, then used his blue Mercedes Benz to transport the body and dispose of it in an unknown location. Mora, who was previously convicted of cocaine possession, is awaiting trial on the murder charge. He maintains his innocence and states he believes Alonzo may still be alive. He said their relationship was sexual but not romantic. In January 2008, Patrice Fluker, a convicted drug dealer, testified that Mora offered him $2,000 to provide him with an alibi in Alonzo's disappearance. Fluker said Mora confessed the murder to him and asked him to say he had seen Alonzo on Thanksgiving Day.

Alonzo left behind five children. She has a troubled history, including arrests for prostitution and drug use. Although her remains have never been recovered, foul play is suspected in her case due to the circumstances involved.