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

After opening 3.23 percent higher, the benchmark Korea Composite Stock Price Index (KOSPI) pared some of its early gains, adding 197.28 points, or 3.05 percent, to 6,668.45 as of 9:15 a.m.

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.

In Seoul, chipmakers led the gains, recouping some of their losses the previous session.

Market bellwether Samsung Electronics rose 4.5 percent, and its chipmaking rival SK hynix jumped 7.93 percent a day after announcing plans to buy back 40 trillion won (US$28.7 billion) worth of shares for shareholder returns.

SK Square, the parent firm of SK hynix, surged 5.98 percent, while Samsung Electro-Mechanics, an electronics component affiliate of Samsung Electronics, slid 0.87 percent.

The Korean won was trading at 1,389.3 won against the U.S. dollar as of 9:15 a.m., down 0.2 won from the previous stock market session's close.