"Can you please leave?" A California woman asks a strange man as he walks out of her home. He responds, "Yes."Oakland, Calif., police now regard this simple yet chilling exchange captured on a cell phone moments before a sexual assault as a key piece of evidence as they search for the intruder.The incident unfolded Tuesday morning when police say a 28-year-old woman was home alone and heard a loud crash."She went to investigate those loud noises and the video shows exactly what she saw," said Oakland police officer Holly Joshi. The victim found the stranger brazenly making an exit from her home with a box full of electronics. He did leave as she requested, but moments later police say he returned and sexually assaulted the woman.Police say she didn't scream or call 911 during the attack, but her presence of mind to film the initial exchange may be the smoking gun that leads to the perpetrator's arrest."She was very much behind the release of the video, she wants justice, she wants the public to be aware of this man so this doesn't happen to another woman," said Joshi.The suspect is described as a black man in his early 40's, 5 feet nine, 160 pounds, with a bald head.Oakland police hope the images, which like so many other pieces of cell phone video has spread virally across the country, will compel someone who knows him to come forward.The victim was treated and released from a California hospital.