Prosecutors are seeking the death penalty against a man charged with kidnapping and killing a 15-year-old Northern California girl whose body has not been found.

Santa Clara County District Attorney Jeff Rosen announced the decision to seek capital punishment against Antolin Garcia-Torres in the 2012 disappearance of Sierra LaMar on Monday. Garcia-Torres has pleaded not guilty to murder and kidnapping charges.

Sierra, who remains missing, was last seen by her family leaving her Morgan Hill home for school in March 2012.

Garcia-Torres was arrested two months later, after authorities say they found Sierra's DNA in his car and his DNA in her handbag.

Sheriff's officials say Sierra and Garcia-Torres did not know each other. Her abduction is believed to be a random act of violence.