Shares in the US fell sharply on Tuesday, as investors fretted that the Federal Reserve could raise interest rates earlier than expected.
A strengthening dollar, which could hurt US exports, also hurt markets.
The Dow Jones fell 332.78 points, or 1.85%, to 17,662.94, while the broader S&P 500 dipped 35.26 points, or 1.7%, to 2044.17. Both indexes erased all the gains made so far in 2015.
The tech-focused Nasdaq shed 82.64 points, or 1.67%, to 4,859.79.
The US dollar continued strengthening, rising 1.4% to 12-year highs against the euro.
The strength of the dollar has worried some investors, because it could hurt the profits of US firms which do business abroad, as their overseas earnings are worth less when converted from foreign currencies.
A strong dollar also makes it harder for US firms to compete with rival firms in other countries, which may be able to offer products more cheaply.
Meanwhile, the looming prospect of an interest rate rise by the Federal Reserve is bad news for some firms, which have benefited from being able to borrow very cheaply as a result of record-low rates.
The falls in US shares echoed earlier falls on European indexes.
Source: BBC