In Nicaragua, President Daniel Ortega has imprisoned all opposition candidates who were set to run in the November 7 presidential polls. Meanwhile, dozens of public figures, party heads and student leaders have been arrested for "treason to the country". Ortega's critics now have only two options: exile or prison. Many are fleeing to Costa Rica, which over the past three years has seen an influx of some 100,000 Nicaraguans. Our regional correspondents report.