Mexican protesters have caused a few border crossing to be closed. They are protesting the regulations for importing a car from the US into the interior (past the border zone) of Mexico. Tijuana and Matmoros are the 2 major ones that are temporarily closed.
http://news.yahoo.com/mexican-protesters-block-key-u-entry-points-mexico-073305106.html
http://www.utsandiego.com/news/2014/dec/08/protest-mexico-traffic-otay-mesa-port-entry/