richmond at the international airport there, it has been evacuated. the action taken after the airport said a serious threat was phoned in. law enforcement agencies, along with canine teams now sweeping that airport, passengers are able to access parking lots and drive out of the airport, of course, we'll update this story as soon as we get more information. antigovernment protests intensifying against a key u.s. ally. >> i can hear some blasts. >> just hours ago, riot police in turkey unleashed tear gas and water cannons on protesters in the capitol city. they are demanding the resignation of their promise and a government that they say is growing more oppressive. cnn's nick paton walsh live in istanbul this morning. good morning. >> reporter: carol, behind me, every few ten minutes or so you do hear, again, tear gas being fired by police as they continue