South Korean shares erased early gains and ended nearly flat on Wednesday as investors took profits after the main index touched a near four-year high.

The Korea Composite Stock Price Index (KOSPI) ended down 0.9 points at 2,143.89, after rising as high as 2,161.23, its highest intra-day level since August 1, 2011. It had closed at 2,144.79 on Tuesday.

Foreign investors bought a net 711 billion won ($658.57 million) of shares on the main board on Wednesday, the highest since September 12, 2013, preliminary exchange data showed.

The won ended local trade up 0.4 per cent at 1,079.6 per dollar from the previous close at 1,083.4.

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