general martin dempsey went to the state department today to talk to secretary of state john kerry about embassy security. the pentagon says u.s. forces are on high alert in the middle east tonight, but fox has learned the marine task force, formed after benghazi, returned to its base in maroney spain from, its forward deployment in italy despite the new terror alert. shepard? shepard: police say they are beefing up security here in new york city because of this terror alert. that says that does not mean that s a specific threat here. they tell us they are being extra cautious. police say they re increasing security at empire state building. houses of worship. when work crews used explosives to knock down a building, somebody made a bad mistake. ahead, the blast that sent metal flying into the crowd and sent five people to hospitals. plus, why would somebody drive a car right down a busy sidewalk? ahead, what we now know about the suspect. and the surveillance video from the scene.