Monterrey, Mexico - In a fourth day of evening-rush-hour street protests against mlitary operations in the region, masked protestors blockaded major streets of this industrial city in northern Mexico and burned a truckload of wooden pallets. The day before, fireworks and molotov cocktails were thrown at police.

Authorities and the media have portrayed demonstrators as tools of the drug cartels, but admit the global economic crisis is a major force behind the unrest. In the past five months, the U.S. consulate and a TV station in Monterrey have been attacked with grenades.