"piers morgan tonight." good evening. you're watching live images here of tahrir square in tie ro where there is an eerie calm. this evening there was heavy gunfire as mubarak clings to power. the american president is pushing for him to go and then there was this -- a video circulating on youtube showing what looks like a white diplomatic van running through a crowd. it happens in a street that appears to lead right into tahrir square. the u.s. embassy said, we are certain no that embassy employees or diplomats were involved in this incident on january 28th. however, a number of our u.s. embassy vehicles for stolen. we have heard reports of their use in violent and criminal acts. if true, we deplore these acts and the perpetrators. let's go to anderson cooper in cairo live tonight. what do you make of that?