U.S. stocks futures were under renewed pressure in early trading Thursday, while European markets extended heavy losses, after a report from Reuters said former National Security Adviser Michael Flynn and others in Donald Trump's Presidential campaign had extensive contacts with Russian officials. 

The Dow Jones Industrial Average was indicated to open more than 50 points lower at the bell, as of 05:30 EST, a move that would take the benchmark's two-day decline past 400 points. The broader S&P 500, which suffered its biggest one-day loss since September yesterday, was priced to open 5.5 points lower.

The losses deepened after a report from Reuters, citing unnamed sources, said that Flynn and other advisers to the President had at least 18 undisclosed contacts with Russian officials and people with ties to the Kremlin in the final seven months of Trump's election campaign.

The revelation follows news last night that the U.S. Department of Justice named former FBI Director Robert S. Mueller to head a probe into allegations that Russia interfered in last year's presidential elections and any ties between the Trump campaign and Moscow.

That comes amid an unprecedented series of events in Washington which have left the White House in seemingly permanent turmoil after Trump fired his former FBI Director, James Comey, who then appeared to suggest in a memo that the President had asked him to shut down an investigation into Flynn, whom he had also fired.

That allegation followed media reports that Trump had shared classified intelligence with Russia foreign minister during a meeting in the White House earlier this year.

The iShares MSCI Eurzone Index ETF (EZU) - Get Report, one of the broadest measures of regional blue chip shares and the latest addition to the Action Alerts PLUS charity portfolio co-managed by TheStreet's Jim Cramer, was marked 1.57% lower at €40.66 each by 10:45 BST, trimming its year-to-date gain to around 15%.

Britain's FTSE 100 was one of the leading benchmark decliners to the downside, falling 1% to extend its two-day slide to just 1.9%. Germany's DAX performance index, however, has slumped more than 2% of the past two sessions and was trading 0.8% lower at 10:45 BST.

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