An El Cajon man stalked a woman by adding GPS technology to her phone, following her into a bathroom stall and even creating a fake Facebook page so he could "friend" her despite a restraining order.
Michael Lutz, 29, pleaded guilty Thursdsay to one count of cyberstalking.
At the time of his arrest, Lutz was in the U.S. Navy stationed in San Diego. He has since been discharged.
Federal prosecutors said Lutz called the woman hundreds of times after she made it clear to him that their romantic relationship was over.
He chased her through a shopping mall, followed her into the women's bathroom and climbed under a locked stall to confront her, prosecutors said.
Lutz used a "keylogger" program on the woman's computer to spy on her prosecutors said.
His sentencing is scheduled for Sept. 19. He faces a maximum of five years in prison.