Fans took to the streets, shutting some of them down. And in Huntington Park, cellphone video shows a fan shooting off fireworks toward police.
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That fan in Huntington Park was later arrested, and two others were also arrested in connection with fan celebrations in Pacoima.
Rowdy behavior was also reported in Santa Ana and East Los Angeles, among other communities. Drivers were seen doing doughnuts on the street, filling the air with smoke and shutting down traffic in some areas.
Mexico beat the World Cup's defending champion Germany, 1-0, on Sunday. The Germans haven't lost a World Cup opening game since 1982.