Wall Street was rattled again today by explosions in Iraq, which killed the president of the Iraqi Governing Council and shook markets around the world.

The bombing that killed Izzedine Salim and several other Iraqis and the discovery of an roadside bomb made from an artillery shell containing sarin nerve gas were new reminders that traders can never count on a business-as-usual day in the stock market.

Crude oil and gasoline prices jumped again in the New York futures markets -- which are even more skittish than the stock markets about world events.

Energy prices set off their own ripples, undercutting stocks of airlines and retailers. With more planes than they can fill and so much competition that it's impossible to pass on higher fuel costs, airlines are being badly pinched as jet fuel prices rise. Shares of Arlington-based U.S. Airways -- regarded as the weakest of the major carriers--fell to $1.50 a share, their lowest price since the airline came out of bankruptcy.

Investors worry that retail spending will suffer because higher gasoline prices are siphoning so much money out of consumers' pockets. Shares of Wal-Mart and Target sold off, along with other retail stocks, but Kmart stock jumped sharply after the company reported its second profit in a row.

Down from the opening bell, the familiar stock indexes fell to new lows for the year.

The Dow Jones industrial average was down for the seventh time in the past nine sessions, closing off 106 points at 9,906.91.

The Nasdaq Stock Market composite index fell almost 28 points to 1,876.64.

The Standard & Poor's 500 stock index lost nearly 12 points, closing at 1,084.08.

External events could drive the stock market all this week, because no new economic data or major corporate profit reports are on the calendar.