Seoul stocks closed sharply lower Friday, ending a three-day winning streak as investors sold technology heavyweights amid external uncertainties including Washington's trade policy. The Korea Composite Stock Price Index fell 123.49 points, or 1.79%, to 6,788.88. Trading was light at 287.6 million shares worth 19.9 trillion won ($14.5 billion), while winners outnumbered losers 638 to 237. The Korean won rose against the U.S. dollar.