Congo authorities block opposition demonstration

By Kenny Katombe KINSHASA (Reuters) - Authorities in the Democratic Republic of Congo blocked an opposition demonstration in the capital on Saturday aimed at putting pressure on President Joseph Kabila to step down next month at the end of his mandate, witnesses said. The rally was banned and heavily armed security forces and large police trucks blocked off key streets. "The sites where the meeting was to have taken place have been isolated," police spokesman Pierre Mwanamputu said in a statemen