Fox News reports:
Egyptian President Mohammed Morsi left the presidential palace Tuesday as violence erupted between police and at least 100,000 protesters gathered in Cairo.
In a brief outburst, police fired tear gas to stop protesters approaching the palace in the capital's Heliopolis district. Morsi was in the palace conducting business as usual while the protesters gathered outside. But he left for home through a back door when the crowds "grew bigger," according to a presidential official who spoke on condition of anonymity because he was not authorized to speak to the media.
The official said Morsi left on the advice of security officials at the palace and to head off "possible dangers" and to calm protesters. Morsi's spokesman, however, said the president left the palace at the end of his work schedule through the door he routinely uses.