A rush for cash shook the financial system Wednesday, as companies and investors hunkered down for a prolonged economic stall, taking the recent market turmoil into a new, more troubling liquidation phase.

Investors sold nearly everything they could in the most all-encompassing market drawdown since the darkest days of the 2008 financial crisis. Short-term money markets at the heart of the financial system were strained and large companies have drawn heavily on credit facilities while they have them.

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