NEW : This means the product will ship as received by the manufacturer, sealed, with all advertised components, and with the manufacturer warranty. The violence was caused by the transfer of prisoners , security official says . Two rival drug gangs collaborated to launch the attacks , he says . The attacks started Sunday in Rio de Janeiro .
NEW : 153 suspects have been arrested since Sunday , police say . The violence was caused by the transfer of prisoners , security official says . Two rival drug gangs collaborated to launch the attacks , he says . The attacks started Sunday in Rio de Janeiro .