Members of a violent Central American street gang have been sent to the southwestern U.S. state of Arizona to attack Minuteman Project volunteers, as they begin a month-long campaign to help patrol the southern U.S. border with Mexico.

James Gilchrist, a Minuteman organizer frustrated by the U.S. government's failure to control illegal immigration, tells the Washington Times newspaper that leaders of Mara Salvatrucha or MS-13 have sent gang members to confront his group in Arizona.

More than 1,000 civilian volunteers are expected to converge on the city of Tombstone Friday to begin a 30-day border patrol. Likewise, Hispanics from the National Alliance for Human Rights are going to Tombstone to protest the Minuteman Project. Last year, 500,000 illegal aliens were caught in Arizona.

MS-13 runs a major smuggling operation on the U.S.-Mexico border, running drugs, weapons and undocumented aliens from Central and South America into the United States.