US equity futures fell about 0.5% on Sunday evening as the war in Iran entered its fifth week and investors prepared for a holiday-shortened trading period. Concerns about a potential resolution to the conflict intensified after Iran-backed Houthi militants in Yemen joined the fighting and additional US troops were deployed to the region. On Friday, the three major US stock averages dropped sharply: the Dow Jones Industrial Average lost 793 points, the S&P 500 slid to a seven-month low and recorded its fifth consecutive weekly decline, and the Nasdaq Composite fell more than 2%.