A big final-hour comeback pulled the Dow Jones industrial average nearly back to where it started Wednesday.
The Dow was down as much as 191 points earlier as the threat of a financial crisis spreading from Europe shook markets. The euro dropped to a nearly two-year low against the dollar, and oil prices sank to their lowest this year.
A late surge of buying erased nearly all of the Dow's deficit, leaving it down just 6.66 points at 12,496.15 by the end of the day. Other indexes ended slightly higher.
In the last hour of trading, news crossed that the leaders of France and Italy favored using regionwide bonds to support Europe's economy. That gave traders hope that a summit of European leaders might produce concrete steps to tackle the economic morass there. The Organization for Economic Cooperation and Development warned on Tuesday that the 17 countries that use the euro risk falling into a "severe recession."
Analysts and investors have turned increasingly skeptical this month that European leaders will prevent Greece from dropping the euro or agree on ways to jump-start the region's economy. The Dow has lost 5 percent this month, nearly wiping away its gains for the year. It has risen only three days in May.