Razor wire sits atop a border fence as a building in the Mexican border city of Tijuana sits behind, as seen from San Diego on Monday, Jan. 31, 2011. (AP Photo/Gregory Bull) ** FILE **

Photo by: Gregory Bull

Razor wire sits atop a border fence as a building in the Mexican border city of Tijuana sits behind, as seen from San Diego on Monday, Jan. 31, 2011. (AP Photo/Gregory Bull) ** FILE **