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By Hayoung Choi and Cynthia Kim
SEOUL, Aug 21 (Reuters) - The Korea Exchange (KRX) said on Tuesday it was monitoring Merrill Lynch's Seoul operations after media reports and petitions regarding the investment bank's trades.
A KRX official said his team was closely monitoring of Merrill Lynch's Seoul operations "as there are public concerns about its high-speed trading".
He declined to comment when asked whether other investment banks' or brokerages' trades were also being monitored. KRX officials declined to be identified, citing internal policies.
Petitions on the website of the South Korean president's office have called for an investigation of the Merrill Lynch's trading of Seoul shares, saying its high-frequency algorithm trading could destabilise markets and leave individual investors at a disadvantage.
Merrill Lynch declined to comment on the KRX's checks.
Merrill Lynch International Incorporated, Seoul Branch, is a subsidiary of Bank of America Merrill Lynch.
Reporting by Hayoung Choi, Cynthia Kim Editing by Eric Meijer