It's an AP article on Yahoo, but here's just a little snippet.
ACALA, Texas – On each side of a towering West Texas stretch of the $2.4 billion border fence designed to block people from illegally entering the country, there are two metal footbridges, clear paths into the United States from Mexico.
http://news.yahoo.com/s/ap/20100819/ap_on_re_us/us_border_bridges