Markets in the US and Asia moved lower overnight as expectations of a weak update from Apple hit technology shares, while tumbling commodity prices impacted mining stocks.
UK stock markets and their European counterparts continued to sell-off today as ongoing worries about global growth and a sharp fall in the US overnight weighed on sentiment.
The US' three major equity markets dropped overnight after a bomb blast at the Boston Marathon shook markets and weak data from China continued to weigh on stocks.
Global markets soared on Wednesday after the US Federal Reserve inadvertently released minutes from its latest policy meeting five hours earlier than planned.
Research and investment house GaveKal Investments has launched a new fund for sophisticated investors that targets capital growth by moving long and short of equity market indices.
Japanese shares have slumped in this morning's trading as equity markets struggle to consolidate gains seen in the first quarter of 2013.
The S&P 500 is on the verge of passing its all-time closing high after rising as much as 0.5% in early trading.
The Dow Jones Industrial Average - one of the two most quoted indices in the US - has hit a record high above 14,200 points, surpassing its 2007 peak.
Gold has suffered the longest run of monthly falls since 1997 after the metal declined for the fifth month in a row in February.