South Korean stocks plunged more than 4% on Monday as investor concerns shot up due to escalating Middle East tensions.

The Korea Composite Stock Price Index, or Kospi, decreased by 304.33 points, or 4.5%, to end at 6,516.27. The Kosdaq also fell by 42.2 points, or 5.3%, to close at 749.64.

The U.S. military said Monday that it carried out a ninth straight night of strikes on Iran, targeting command centers, air defenses, missile facilities and other military infrastructure, while a U.S. service member died in northern Iraq during the controlled disposal of an unexploded Iranian drone.

Several locations in Bushehr, the capital of Iran's southwestern Bushehr province, were hit in an attack, the province's governor said, Mehr News Agency reported.

In economic news, the per capita gross domestic product (GDP) of South Korea is estimated to increase 7.6%, or up $2,750, on-year to about $39,164 this year, Yonhap News reported Sunday, citing data from local analysts.

The projected per capita GDP growth will be the strongest annual jump since the 11.5% recorded in 2021, according to the report.

In corporate news, the brand value of Samsung Group, the parent group of Samsung Electronics (KRX:005930) and Samsung Biologics (KRX:207940), jumped 8.9% to $97.4 billion in 2026 from $89.4 billion in 2025, British consulting firm Brand Finance said in a Sunday report.

The group ranked eighth in Brand Finance's ranking of the top 100 tech companies globally.

SK Hynix (KRX:000660) rose one place to 28th, LG Corp (KRX:003550) slipped eight spots to 44th, Coupang slipped one position to 49th, and Naver (KRX:035420) moved up five places to 95th, according to the report.

Shares of Samsung Electronics and SK Hynix fell nearly 4% at market close, while Samsung Biologics declined 3%. Shares of Naver fell over 2% at market close.