Stock markets plunged around the world Monday as investors worried about the Russian military takeover of Ukraine's Crimean peninsula.
The selloff started in Asia and quickly spread through European and U.S. exchanges, with most dropping one percent or more.
The economic fallout was pronounced in Moscow, where the stock market fell more than 11 percent, erasing nearly $60 billion off the value of Russian companies.
The value of the Russian currency, the ruble, dropped to an all-time low against the U.S. dollar, prompting the Russian central bank to boost its key lending rate 1.5 percent.
World political turmoil frequently sends stock markets into a plunge. But it is unknown how long the concern might last over President Vladimir Putin's dispatch of Russian troops into Crimea.
Russian Deputy Economy Minister Andrei Klepach called the plunging stocks a market "hysteria" and said it would subside.
The chief executive of a British investment brokerage, Nigel Green of deVere Group, said he thinks the stock sell-off will prove to be short-lived, with investors ultimately deciding that the Russia-Ukraine conflict is "a local issue."
But the United States and its European allies have threatened to impose visa bans and trade restrictions and to impose asset bans that could further roil international markets in the coming days.
Ukraine is in severe economic straits, and Kyiv is seeking new funding from the International Monetary Fund, the United States and the European Union . Ukraine says it need $35 billion in new funding during the next two years.