Seoul shares opened higher Thursday, tracking overnight gains on Wall Street as U.S. Treasury yields eased on plans for increased debt buybacks.

The benchmark Korea Composite Stock Price Index (KOSPI) added 209.17 points, or 3.23 percent, to 6,680.34 at the opening bell.

The index plunged nearly 6 percent the previous session on tech sell-offs amid woes over rising bond yields.

Overnight, Wall Street's major indexes closed higher as U.S. Treasury yields retreated after the Treasury Department announced plans to significantly increase buybacks of longer-term government debts.

The yield on the 30-year Treasury bond, which had climbed to its highest level since 2007, fell Wednesday along with the benchmark 10-year Treasury yield.

The Dow Jones Industrial Average rose 0.22 percent, and the S&P 500 added 0.21 percent. The tech-heavy Nasdaq Composite Index climbed 0.16 percent.

Investors are also betting that chip giant SK hynix will get a boost from its plans to buy back 40 trillion won ($28.7 billion) worth of shares for shareholder returns.