Sorry if this has been brought up before (or several times before), but I was playing around on a solo game and was at war with Ramesses at one point in the game. Upon capturing the city of Alexandria, the screen suddenly shifted onto Heliopolis which appeared to be captured by me as well, but I have no clue as to why. If you notice in the second screenshot, Ramesses still has troops in Heliopolis, despite still being at war.

http://i16.photobucket.com/albums/b29/Kodi_87/Civ4ScreenShot0000.jpg

http://i16.photobucket.com/albums/b29/Kodi_87/Civ4ScreenShot0001-1.jpg

this belongs in the bts bug reports section. it is a known bug caused by teleporting workers and has been fixed in bhruic's unofficial patch - install it and all is well :)