Seoul shares opened lower Friday, tracking overnight losses on Wall Street as U.S. Treasury yields again rose and higher oil prices weighed on investor sentiment. The benchmark Korea Composite Stock Price Index (KOSPI) fell 92.63 points, or 1.35 percent, to 6,759.95 at the opening bell. U.S. Treasury yields resumed their upward trend Thursday, reversing much of the previous day's decline following the U.S. Treasury's announcement of an expanded bond buyback plan. The rebound came as investors grew skeptical that the expanded buybacks would provide more than temporary relief from rising long-term borrowing costs. Overnight, the Dow Jones Industrial Average shed 1.32 percent, while the S&P 500 slipped 0.87 percent. The tech-heavy Nasdaq Composite Index fell 1 percent. Higher oil prices added to the downward pressure on stocks, with Brent crude rising more than 2 percent amid renewed U.S.-Iran tensions.