Congo authorities block opposition demonstration

KINSHASA (Reuters) - Authorities in 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 security forces maintained a heavy presence. They also prevented activists and the U.N. peacekeeping mission in Congo from approaching the house of veteran opposition leader Etienne Tshisekedi, witnesses said. (Reporting by Ken