The KOSPI closed above the 9,000 mark for the first time. Strength in heavyweight semiconductor shares combined with foreign buying to set new records both intraday and at the close.

The KOSPI ended up 199.60 points, or 2.25 percent, at 9,063.84, the Korea Exchange said on June 18. It rose as high as 9,106.07 during the session, setting a new 52-week high.

The KOSPI has risen for five consecutive sessions. After topping 4,000 last October, it broke through 5,000 in January, 6,000 in February, and 7,000 and 8,000 in May, and then crossed 9,000 about a month later. It has gained more than 110 percent since the start of the year.

Semiconductor shares led the rise in the index on the day.

Samsung Electronics ended up 4.62 percent at 362,500 won and SK Hynix gained 6.51 percent to close at 2,685,000 won, with both posting record highs. Samsung Electro-Mechanics, SK Square and Samsung Life Insurance also showed strength.

Still, advancing issues on the main board totalled 109, while decliners numbered 791, prompting analysis that the rise in the index was concentrated in a handful of heavyweight stocks such as semiconductors.

Foreign investors were net buyers of 1.28 trillion won, lifting the index. Retail investors and institutions were net sellers of 380.6 billion won and 777.5 billion won, respectively.

A hawkish stance was confirmed after the U.S. FOMC meeting, but the domestic stock market's upward trend appeared to continue.

Some in the brokerage industry are also forecasting that the KOSPI's upper range could rise above 10,000, based on the semiconductor cycle and foreign inflows.