There has been a major breakthrough in the investigation into murder of lawyer Anat Pliner, police said Friday morning. A gag order has been placed on the details of the probe. Pliner, a Ramat Hasharon real-estate lawyer and mother of two, was stabbed on her front doorstep in April 2006. The assailant knocked on the door, stabbed Pliner in the stomach and then fled. Police initially said they were unsure of the motive for the attack.