European markets closed sharply lower on Friday, pressured by Chinese futures which were down heavily and mounting tensions over Greece debt negotiations.
The pan-European Euro Stoxx 600 index closed around 1.8 percent lower, as "risk-off" sentiment continued, despite stellar gains for much of the year.
Some traders said that markets had sold off sharply due to speculation that the Chinese government had asked investors to "take froth out of the market".
China also allowed fund managers to lend shares for short-selling on Friday and will expand the number of stocks investors can short sell, in an effort to raise the supply of securities in the market, according to Reuters.
German stocks saw the brunt of the selling, with the DAX losing around 2.6 percent, following losses of around 1.8 percent on Thursday, bringing weekly losses to around 5.6 percent. Year-to-date the DAX has rallied 20 percent.
This came after Bloomberg's trading terminal experienced an outage on Friday morning, with some users unable to perform their usual trading activity. By 12:45 p.m. London time Bloomberg said the service had been restored to most customers and it was making progress to bring the full network back online.
A trader at Amplify Trading in London said the issue had hit trading liquidity on Friday and accentuated the "risk-off" sentiment seen in several asset markets during the morning session.
U.S. stocks traded sharply lower on Friday, following the trend in European markets.
Greek stocks closed around 3 percent lower Friday. Euro zone finance ministers are due to meet on April 24 to discuss Greece making economic and political reforms in return for aid. Some officials, like German Finance Minister Wolfgang Schaeuble, are skeptical the meeting will yield results.
In U.K. news, unemployment data out on Friday showed that the jobless rate had hit its lowest level since July 2008.
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