Vikings quarterback Brett Favre is the subject of an NFL investigation into allegations that he sent lewd photographs and suggestive messages to a female New York Jets employee in 2008, a development that first put his streak in danger with the possibility of a suspension under the league's personal conduct policy. NFL spokesman Greg Aiello said Monday there was nothing to report about the investigation, but league sources told ESPN NFL Insider Adam Schefter that the league could end its investigation this week. Thus far, Jenn Sterger, the woman at the center of the probe, has not cooperated with the NFL and according to the sources, the league nearly closed the investigation after Favre spoke to NFL security in Minneapolis last week. Fox News reported Sunday that Favre admitted to the league that he left voicemails for Sterger, but denied sending the photographs. The NFL left the investigation open in the event that Sterger would agree to step forward and share her story with the NFL, but the league is comfortable with the people it has interviewed and the information it has gathered, the sources said. Source: ESPN