S.F. woman, 43, accused of killing teenager she dated

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  A 43-year-old woman pleaded not guilty Friday to shooting and killing an 18-year-old man in San Francisco’s McLaren Park, as authorities revealed that the two had been in a romantic relationship before the alleged attack.
  Silvia Lorena Montoya is charged with one count of murder and three counts of dissuading a witness in connection with the May 31 killing of Jonathan Caballero.
  
  Police responding to reports of shots fired at McLaren Park that morning found Caballero, a Balboa High School student, unconscious and bleeding from at least one gunshot wound on a walking trail off John F. Shelley Drive.
  
  He died at the scene. Investigators spent the next two months gathering evidence that led them to Montoya, police officials said, and she was booked into county jail on July 30.
  
  Authorities have not discussed a possible motive, but prosecutors said Montoya and Caballero had dated. Kwixuan Maloof, a managing attorney in the public defender’s office who is representing Montoya, said Caballero had lived with Montoya at some point.
  
  In court Friday, Montoya stood quietly as Maloof requested the names of the three witnesses she is accused of dissuading. Assistant District Attorney Patrick Mahoney said his office had to ensure the witnesses’ safety before he could identify them to the defense.
  
  Montoya flashed a small wave at two women and a man sitting in the back of the courtroom before she was led back to a holding cell.
  
  The victim’s relatives also attended the hearing, with one woman tearing up as they declined to comment outside court.
  
  Maloof said he could not comment on Montoya’s defense until he received more evidence from the district attorney’s office. But he said statements from witnesses contradicted each other, and that the police report on the homicide made no mention of dissuading witnesses.
  
  Montoya is being held on $10 million bail. She is scheduled to return to court Monday.