. >> we are told that it is very rare, unfact it is unprecedented. they didn't think of another time when this kind of widespread complete district closure has happened. it just points to the fact that there is an abundance of caution happening right now. they are hoping to find out what exactly it is, but the threat is so specific, that it made them take on this sweeping closure to keep everyone safe. >> dena thank you very much. we should point out that this is a threat, a threat only so far, other than the fact that the threat seems to be more specific than in years past. you heard the former police chief saying when he was on his watch, there were so many threats that they had to start separating them because people were using them simply as a way to get out of work on friday. >> today is the last day for americans to sign up for obamacare. the obama administration is hoping to sign up about 900,000 people through the affordable care act this year. that would bring the total number of people covered to 10 million. according to this morn's "new yo