U.S. stocks on Tuesday extended losses from a bruising previous session in which the S&P 500 confirmed a bear market as investors braced for an aggressive interest rate hike by the Federal Reserve this week.

The U.S. central bank is expected to raise rates by 75 basis points on Wednesday after a hotter-than-anticipated rise in consumer prices in May.

Shares on Wall Street's main indexes have lost between 16% and 30% of their value this year amid economic uncertainty stoked by supply chain and labor shortages, soaring inflation, the fallout of Ukraine war and an aggressive monetary policy.

Eight of the 11 major S&P sectors fell, with defensive sectors such as utilities, real estate and healthcare leading the selloff. The energy sector topped the list of gainers with a 2.1% rise.

Among megacap growth stocks, Amazon fell 0.2%, while Tesla rose 2.7%.

In a day of volatile trading, data that showed core producer prices cooled slightly on a year-over-year basis in May lifted sentiment, but it was short-lived.

"Take a look at what the markets look like - interest rates are a little bit higher, the yield curve is extremely flat, the producer price index came in a little bit better than expected, but not much to really cheer about," said Paul Nolte, portfolio manager at Kingsview Investment Management in Chicago.

"There is a lot to digest and investors are skittish. Not many want to be too aggressive in front of the Fed meeting given the possibility that they raise rates by 75 basis points at tomorrow's meeting."

At 12:15 p.m. ET, the Dow Jones Industrial Average was down 247.75 points, or 0.81%, at 30,268.99 and the Nasdaq Composite was down 1.53 points, or 0.01%, at 10,807.69.

The benchmark S&P 500 was down about 19 points, or 0.5%, at 3,732, after closing 20% below its all-time closing high on Jan. 3.

If session losses hold, the index is looking at a five-day streak of declines, its longest since the beginning of the year.

Among individual stocks, FedEx Corp leaped 12.8% after raising its quarterly dividend by more than 50%, while Oracle Corp added 8% after posting upbeat quarterly results on demand for its cloud products.

Continental Resources Inc jumped 14% after the shale producer received an all-cash buyout offer from its founder Harold Hamm, valuing the company at $25.41 billion.

Declining issues outnumbered advancers for a 1.59-to-1 ratio on the NYSE and for a 1.26-to-1 ratio on the Nasdaq.

The S&P index recorded two new 52-week highs and 68 new lows, while the Nasdaq recorded eight new highs and 511 new lows.