NEW YORK (Reuters) - U.S. stocks hit session lows in early afternoon trading on Thursday, with the S&P 500 on track to post its worst day in six weeks, as tension over Ukraine's Crimean peninsula mounted.
The Dow Jones industrial average fell 177.34 points or 1.09 percent, to 16,162.74, the S&P 500 lost 17.54 points or 0.94 percent, to 1,850.66 and the Nasdaq Composite dropped 57.698 points or 1.33 percent, to 4,265.634.
Ukraine's acting president said Russian forces were concentrated on the border "ready to invade" his country but he believed international efforts could end Moscow's aggression and avert the risk of war.
(Reporting by Rodrigo Campos; Editing by Meredith Mazzilli)
