US stocks tumble at open as oil prices touched $100 per barrel amid Iran conflict

US stock markets plunged on Thursday as surging oil prices and escalating conflict involving the US, Israel, and Iran rattled investor confidence. Dow Jones Industrial Average fell 1.1 per cent to 46,879.09 while S&P 500 declined 1.0 per cent. Crude prices briefly surpassed $100 per barrel amid fears of Middle East supply disruptions, with no end in sight to the ongoing hostilities.