Sonia, a Bolivian immigrant, sews clothes at her house, in the Bras neighbourhood of Sao Paulo August 19, 2013. In Sao Paulo, the country's business centre, the number of immigrants from other South American countries more than doubled between 2000 and 2010 to over 23,000, according to the Brazilian statistics agency IBGE. However, unofficial estimates by city officials put the number at between 200,000 and 400,000. Alarmed by soaring reports of labor abuses as the migrants flowed in, Brazilian officials in 2009 tried to bring immigrants out of the shadows by signing a regional agreement that made it easier for many of them to receive work visas. Picture taken August 19, 2013. To match Feature BRAZIL-IMMIGRANTS/ REUTERS/Nacho Doce (BRAZIL - Tags: BUSINESS SOCIETY IMMIGRATION EMPLOYMENT)