republicans who say it violates u.s. law. we will take you to libertyya s capital early this friday morning, june 17th, 2011. captioning funded by cbs good friday morning. welcome to a live west coast update of the early show it. i m erica hill. i m chris wragge. a security alert outside the pentagon today. one person is under arrest. police are searching the area. after finding a suspicious vehicle. cbs news national security correspondent david martin is at the pentagon with the very latest for us this morning. david, good morning. reporter: good morning. a spokesman for the fbi has just said that no explosive devices were found after this incident this morning here at the pentagon, which shut down morning rush hour traffic for hours. here is what happened. a man carrying a backpack was spotted overnight in arlington national cemetery which is closed after dark. when police approached him, he fled. he was arrested and both his backpack and his vehicle have now bee