A Zetas leader arrested in the streets of Nuevo Laredo is being accused of masterminding the Falcon Lake murder of American tourist David Hartley and the massacres in San Fernando. Mexican marines arrested Salvador Alfonso Martínez-Escobedo in Nuevo Laredo around 7 p.m. Saturday. Martinez-Escobedo, who goes by the nickname "La Ardilla" or "The Squierrel", is reported to be a regional commander for the Zetas drug cartel. Mexican Navy officials report he escaped from gun battle with marines that left one person dead in the San Agustin subdivision early Saturday morning. Marines found Martinez-Escobedo hours later in an SUV in the...