OAKLAND, Calif. (AP) - A murder trial is underway for a woman accused of stalking and killing a San Francisco Bay area nursing student.

Alameda County Prosecutor Butch Ford argued Monday that Giselle Esteban killed former friend Michelle Le last year out of "jealousy, hatred and rage," because she blamed Le for ruining her relationship with Scott Marasigan, her daughter's father.

Ford said Esteban texted Marasigan that "punishment would be swift" if he didn't cut Le out of his life. Ford also said that Esteban went to great lengths to hunt Le down, including stealing a security badge and a class roster from Le's nursing school.

But Esteban's defense attorney, Audrea Aura, admitted while there's "a mountain of evidence" against her client, Esteban did not plan to kill Le, but snapped due to "extreme provocation and heat of passion."

Esteban has pleaded not guilty.

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