An elderly protester carries a Venezuela's flag during a march for peace in downtown CaracasBy Brian Ellsworth and Andrew Cawthorne CARACAS (Reuters) – Anti-government demonstrators set up barricades in Venezuela’s capital on Monday, snarling traffic, despite calls from within the opposition to rein in protests in which at least 11 people have died in the OPEC nation. Traffic slowed to a crawl around Caracas, and many people stayed at home, as protesters burned trash and piled debris along main avenues a day after opposition leader Henrique Capriles called on them to keep demonstrations peaceful. The most sustained unrest in Venezuela for a decade is the biggest challenge to President Nicolas Maduro’s 10-month-old government, though there is not sign it will topple him nor affect oil shipments from Latin America’s biggest exporter. “If there’s one thing these violent protests have done, it’s unite ‘Chavismo’,” Maduro said on Sunday night, using the term for government supporters coined during the 14-year rule of his predecessor, Hugo Chavez.