The Federal Reserve Bank of New York will run its fourth so-called repo operation of the week to inject cash into Wall Street's funding markets Friday, according to a statement from the bank.

The operation will inject another $75 billion into the credit system "in order to help maintain the federal funds rate within the target range of 1-3/4 to 2 percent," according to the statement.

Combined with the earlier operations this week, the bank will have injected $278.5 billion into the credit system this week. These have been the first such operations by the Fed since the credit crisis more than 10 years ago.

The $2.2 trillion repo market, a key source of day-to-day financing on Wall Street, was rocked earlier this week by a massive spike in overnight borrowing costs linked to a series of events, including quarterly tax remittances, which drained money market funds, and record Treasury bond issuance.

Fed Chairman Jerome Powell said at his post-FOMC news conference Wednesday that "The strains in the money markets reflect forces that we saw coming, and they just had a bigger effect than I think most folks anticipated: strong demand for cash to purchase Treasuries and pay corporate taxes."

The Fed cut its key lending rate by 25 basis points to between 1.75% and 2% on Wednesday, in a widely anticipated move.