NEW YORK (CNNMoney.com) -- Stocks fizzled at Wednesday's open, the recent enthusiasm over cooling inflation struck by a seventh missile test launch by suspected nuclear power North Korea.

The Dow Jones Industrial average and the broader Standard & Poor's 500 index both fell about 0.6 percent just after the open. The Nasdaq composite lost about 1 percent.

The seventh test, believed to be a medium range ballistic missile, came just hours after six other tests drew sharp international critics.

One of those tests was of a long range rocket that some analysts say could hit the western U.S., although the rocket managed to fly just 200 miles. (full CNN coverage)

The events have shaken world markets, already jittery over other geopolitical tensions including a spat with Iran over its nuclear program.

European markets fell in midday trade and Asian markets ended lower.

In corporate news, the Big 3 automakers began reporting monthly U.S. sales figures Monday. Ford (Charts) said U.S. sales fell 7 percent in June, while DaimlerChrysler (Charts) said its U.S. vehicle sales fell 13 percent during the month. After the market close, General Motors (Charts) said its June sales sank 26 percent.

Renault and Nissan Chief Executive Carlos Ghosn is set to meet his counterpart at GM, Rick Wagoner, later this month in Detroit to discuss areas of potential cooperation, according to the Financial Times. (Full story.)

Atlantic City's casinos, which cannot operate without state regulators, have been ordered closed by the state's Casino Control Commission due to New Jersey's budget crisis.

Properties owned by Trump Entertainment Resorts (Charts), Harrah's Entertainment and Hilton Hotels as well as the Borgata, a joint venture by MGM Mirage (Charts) and Boyd Gaming (Charts) will all be affected. (Full story.)

Treasury prices were mostly lower, with the yield on the 10-year note rising to 5.21 percent from 5.16 late Monday.

Oil was mixed, with U.S. light crude futures down 2 cents to $73.91 a barrel, while Brent crude was up 54 cents to $73.05.