Enough circumstantial evidence to point to it being Russia.
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Billions of dollars in foreign owned currency holdings have been pulled out of the United States and there’s growing suspicion that the culprit is Russia attempting to circumvent any sanctions that the US may levy against the nation over the intensifying Ukrainian situation.

The Federal Reserve custody holdings report which documents “Foreign central banks’ holdings of U.S. marketable securities” has fallen to the lowest level since December 2012 with more than $100 billion being removed in the week ending on Wednesday, March 13.

The Federal Reserve has not divulged the party or parties responsible, but insiders believe that there is enough circumstantial evidence to point to it being Russia — even though the amount withdrawn hasn’t yet appeared in Russian hands.