Dealers work in the dealing room of Hana Bank headquarters in Seoul, Monday, after a circuit breaker was triggered on the KOSPI amid a sharp market selloff. Yonhap

Korean stocks tumbled Monday, as a broad-based correction in global semiconductor shares triggered heavy selling across the market, prompting the activation of both sidecar trading curbs and circuit breakers on the KOSPI and Kosdaq markets.

Attention is centered on whether KOSPI, which has staged a record-breaking rally this year, can resume its upward trajectory after a short-term correction or whether market volatility will intensify further.

The benchmark KOSPI opened 112.50 points, or 1.38 percent, lower at 8,048.09 before extending its losses throughout the session to close at 7,484.41, down 676.18 points, or 8.29 percent.

The index reached an all-time intraday high of 8,933.62 on June 2. After plunging 5.54 percent on Friday, the KOSPI posted losses for a second consecutive session, underscoring growing concerns over a pullback in semiconductor stocks that had fueled the market's recent rally.