U.S. stock benchmarks rang up another solid session of losses, sparked by growing concerns about the omicron variant of the coronavirus that causes COVID-19 and comments from Federal Reserve Chairman Jerome Powell. The Dow Jones Industrial Average /zigman2/quotes/210598065/realtime DJIA -0.28% ended the session off 1.9% to about 34,484, bringing the blue-chip index about 5.3% below its Nov. 8 closing record and dragging the index nearer a correction, defined by chart technicians as a 10% drop from a recent peak. The S&P 500 index /zigman2/quotes/210599714/realtime SPX -0.67% closed down 1.9% to 4,567 nearly 3% below its Nov. 18 record peak and the Nasdaq Composite Index /zigman2/quotes/210598365/realtime COMP -1.21% declined 1.6% to 15,537. The small-capitalization Russell 2000 index /zigman2/quotes/210598147/delayed RUT -1.77% appeared to narrowly avoid a correction, which would stand at around 2,198 for the small-capitalization index. Equities were already feeling pressure after Moderna Inc.'s chief executive officer predicted that current vaccines would be less effective against the new omicron variant of the coronavirus that causes COVID-19. Losses deepened after Federal Reserve Chairman Jerome Powell told lawmakers that it would be appropriate for policy makers to consider winding down monthly asset purchases more quickly than planned.