LOS ANGELES, CA - FEBRUARY 13: Some demonstrators carry pictures of Mario Aburto Martinez during a demonstration against Mexican President Felipe Calderon's visit with Los Angeles Mayor Antonio Villaraigosa on February 13, 2008 in Los Angeles, California. Martinez had assasinated Luis Donaldo Colosio Murrieta, a presidential hopeful, during a campaign rally in Mexico in 1994. President Felipe Calderon of Mexico dined with Mayor Antonio Villaraigosa of Los Angeles during the last leg of Calderon's U.S. tour. Calderon has exhorted Americans to treat Mexican immigrants with respect and dignity but activists take issue with a range of policies held by Calderon and his PAN party including the support of the North American Free Trade Agreements which they say has hurt Mexican farmers, devastated large portions of the job market, and increased massive illegal immigration of unemployed Mexicans seeking jobs in the US.