The benchmark Korea Composite Stock Price Index and foreign exchange rate are displayed on a screen at Hana Bank's dealing room in Seoul on Friday.(Yonhap) The country's bourse operator on Friday activated a sell-side sidecar for the benchmark Korea Composite Stock Price Index as the index nosedived due to a slump in tech heavyweights.Program trading for the KOSPI was suspended for five minutes at around 9:08 a.m., according to the Korea Exchange.The KOSPI fell sharply as investors took a breather following a recent rally in tech shares amid uncertainty over the US-Iran peace deal.Opening at 3.66 percent lower, the KOSPI fell as low as 8,146.65 at one point, or 5.7 percent.Tech stocks and other major market heavyweights suffered sharp declines as investors cashed out following record-breaking rallies.A sell-side sidecar is triggered when the KOSPI 200 Futures index decreases 5 percent or more for at least one minute. (Yonhap)