General Randy George has been removed as chief of the US Army in a sudden military reshuffle under President Donald Trump's administration. The decision, confirmed by Pentagon spokesman Sean Parnell, takes effect immediately, with George retiring after nearly 40 years of service. He led the army during ongoing US military operations against Iran, which Trump has indicated will continue for weeks. No detailed reason was given for the removal. General Christopher LaNeve will serve as acting chief of staff, described by Defence Secretary Pete Hegseth as "a battle-tested leader with decades of operational experience." Two other senior officers, General David Hodne and Major General William Green Jr, were also removed. This follows Trump's earlier dismissal of Joint Chiefs of Staff Chairman General Charles Q. Brown Jr, also without explanation. The changes are part of a broader turnover in top military leadership since Trump returned to office about a year ago. George previously served as vice chief of staff and senior military assistant to former defence secretary Lloyd Austin, with combat deployments in Iraq and Afghanistan. Hegseth defended the moves, saying the president is appointing leaders he trusts. Some lawmakers have expressed concern over the frequency and lack of transparency in the dismissals.