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KOSPI falls for third straight session

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Korean won weakens against dollar

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South Korea benchmark bond yield surges

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For the midday report, please click

SEOUL, Oct 21 (Reuters) - Round-up of South Korean financial markets:

** South Korean shares ended slightly lower on Friday and ended the week flat, amid concerns over U.S. Federal Reserve's aggressive monetary tightening. The Korean won weakened, while the benchmark bond yield hit an 11-1/2-year high.

** The benchmark KOSPI ended down 4.97 points, or 0.22%, at 2,213.12, falling for a third session. The index ended the week with a marginal gain of 0.03%.

** Fed Bank of Philadelphia President Patrick Harker said the central bank is not done with raising its short-term rate target amid redhot of inflation, sending stocks lower and bond yields up sharply.

** "The Fed's aggressive tightening and a rise in U.S. Treasury yields increased downward pressure on the stock market, but losses were capped with the issue having been there for a while by now," said Lee Kyoung-min, an analyst at Daishin Securities.

** Technology giant Samsung Electronics rose 0.72% and peer SK Hynix gained 0.33%, while automakers Hyundai Motor and Kia Corp lost 0.89% and 0.73%, respectively.

** Battery maker Samsung SDI jumped 6.45%, its biggest daily gain since March 2021, while peers LG Energy Solution and SK Innovation advanced 0.81% and 0.65% each.

** Of the total traded issues of 932, only 172 advanced.

** Foreigners were net buyers of shares worth 22.5 billion won ($15.62 million).

** The won was last quoted at 1,439.8 per dollar on the onshore settlement platform, 0.45% lower than Thursday. The currency weakened for a second week with a 0.79% weekly loss.

** December futures on three-year treasury bonds dropped 0.34 point to 101.15.

** The most liquid three-year Korean treasury bond yield rose as much as 18.1 basis points to hit a more than three-week high of 4.500%, while the benchmark 10-year yield jumped as much as 25.0 bps to 4.665%, its highest since March 2011. ($1 = 1,440.3500 won) (Reporting by Jihoon Lee; Editing by Rashmi Aich)