DALLAS Apr 25, 2007 (AP)— A massive spring storm plowed toward the Midwest early Wednesday after dumping more than a foot of snow on the Colorado foothills and spawning a tornado that killed nine people along the Texas-Mexico border. Six of the victims were killed a few miles south of Eagle Pass, about 150 miles southwest of San Antonio. Four of the dead were apparently in one mobile home when the tornado hit Tuesday night, Eagle Pass Mayor Chad Foster said. The tornado destroyed an elementary school, more than 20 nearby homes and the Eagle Pass municipal sewer treatment plant. Nobody was in the school when the tornado hit, Foster said. "I'm out here on-site and I'm looking at what used to be an elementary school," Foster said by cell phone early Wednesday morning. "Six mobile homes are still missing." A local hospital received 74 injured patients, including four in critical condition. Across the border in Piedras Negras, Mexico, at least three people were killed and at least 40 were injured in the severe weather, authorities said. The storm ripped roofs from homes, toppled power poles and damaged dozens of cars and homes, said Oscar Murillo, the city's civil protection director. In North Texas, streets flooded and roofs peeled off homes as storms began moving through Tuesday afternoon, followed by another line of severe storms about six hours later. Tornado sirens rang in several counties, and television footage showed drivers and residents being rescued from flooded cars and suburban neighborhoods. American Airlines had about 200 flights canceled because of weather in Dallas, spokesman Billy Sanez said. The airline also diverted about 80 flights bound for Dallas-Fort Worth International Airport to other airports, including San Antonio. In Denton County, heavy winds blew the metal roof off a restaurant and damaged several mobile homes and a commercial building under construction, said Roland Asebedo, assistant chief for Denton County's Emergency Services. No injuries were reported.