Thousands of anti-government protesters barricaded Thailand's parliament Tuesday, leading to clashes with riot police and to the deployment of troops to curb political unrest on the streets of Bangkok.

Hours after angrily chiding federal prosecutors for an evidence-withholding mistake, a federal judge in Washington rejected a request on behalf of Alaska Sen. Ted Stevens to dismiss corruption charges or declare a mistrial Thursday afternoon.

Since undertaking market reforms in late 1970s, China has enjoyed an economic boom -- but the economic progress has also produced serious environmental damage and pollution problems. Margaret Warner reports on China's environmental woes and their impact on the run-up…