SAN LUIS, Mexico (KYMA) - Hundreds of teachers from various areas in Sonora took part in a protest Thursday morning. This included the temporary closure of the San Luis, Río Colorado international border crossing, as part of actions led by the Sonoran Education Workers' Movement. The teachers gathered at one of the country's key border crossings to demand the repeal of the 2007 ISSSTE Law, as well as changes to the pension and retirement system …