A plunge in Chinese stocks rippled across global markets Tuesday, triggering a massive wave of selling in the United States that sent the Dow Jones industrial average down 3.3 percent, or 416 points, its biggest decline since March 2003.

The news from Asia sparked the initial sell-off, but a confluence of other events, including news of rising real estate loan delinquencies, a surprisingly weak manufacturing report and a bombing near Vice President Dick Cheney in Afghanistan, made an already difficult day worse.

For most of the morning the Dow declined steadily until it had fallen 300 points. Then, just before 3 p.m., it suddenly plummeted another 200 points before recovering slightly because of a trading glitch that led to a backlog of sell orders clearing at once. The Standard and Poor's 500-stock index, a broad measure of stock prices, also lost more than 3 percent by the close of the trading day, its biggest drop in three and a half years.