Dan Driscoll has been in the job for 18 months, and no reason has been given for his exit. He's reportedly endured a tense relationship with Defence Secretary Pete Hegseth.
A source told Reuters news agency that Mr Driscoll had "brought up concerns with the administration surrounding Army transformation and readiness", with Mr Hegseth "blocking those efforts" by "firing the generals responsible".
The US army is yet to comment on the news, which was first reported by The Wall Street Journal.
The Trump administration has seen a large amount of turnover among America's military leadership. Last year the president pushed out the country's most senior commander and several other admirals and generals.
Since the war with Iran began in February, Mr Trump has also lost his navy secretary, John Phelan; director of national intelligence, Tulsi Gabbard; and senior counterterrorism official, Joe Kent.
Mr Hegseth has in recent months also personally disposed of the army's top uniformed leader, Randy George, and its commander for Europe and Africa, Christopher Donahue.
An ally of Mr George, Mr Driscoll had lamented his departure, telling Congress in April that he and his family had driven to Mr George's house following his resignation and "all gave him a hug".
"That being said, the civilian leadership, the design of our system, is that they get to pick the leaders that they want," Mr Driscoll added.
A 'change agent'
The White House said in a statement that Mr Driscoll had provided "outstanding leadership during historic military operations", and he left with the US army "more powerful than ever".
In his role as army secretary, Mr Driscoll was tapped for the role of key negotiator to try to end the war between Russia and Ukraine.
He was also a major force behind trying to cut the red tape for military contractors to quickly develop more drones and counter-drone capabilities.
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An Iraq war veteran, Mr Driscoll is a former adviser to Vice President JD Vance, whom he met at Yale Law School.
When nominating Mr Driscoll in 2024, Mr Trump called him "a disruptor and change agent".
According to the army, Mr Driscoll served as an armour officer from August 2007 to March 2011, deploying to Iraq from October 2009 to July 2010.
He also ran unsuccessfully in the Republican primary for a North Carolina congressional seat in 2020, receiving around 8% of the vote.
The annual Caribbean festival in west London was celebrating its 60th anniversary over the weekend, with the main parade taking place on Bank Holiday Monday.
The Metropolitan Police described the atmosphere as "overwhelmingly positive and celebratory" and said it "passed largely without incident".
However, as of Monday night, there had been 560 arrests over the course of the two-day event, and the Met said it expected that number to rise.
'Serious violence' down for second year
Some 48 of the arrests followed identification using live facial recognition, controversial technology which is being rolled out to forces across the country.
Stop and search was also used extensively, with a handgun among 62 weapons seized. There were still two knife attacks, though neither resulted in life-threatening injuries.
Commander Claire Smart, the Met's top cop for the carnival, said: "This is the second year now that we have seen a marked difference in the prevalence of serious violence."
She said this was down to "proactive policing" and collaboration with organisers, who she praised for taking on many event management and crowd safety roles previously performed by the police.
Man dies after entering canal
The Met also revealed details of a police chase which ended with a man dying after entering a canal.
Officers had attempted to stop the man, believed to be in his 20s, as he approached the event at around 3.20pm.
He fled on foot with officers in pursuit near Harrow Road and entered the water near Meanwhile Gardens.
Officers and members of the public pulled him from the water. He required medical attention, and paramedics were called before he was taken to a central London hospital. He was pronounced dead at around 4.45pm.
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Commander Smart said: "I acknowledge the efforts of the officers and members of the public who entered the canal to rescue this man. I know they will be devastated that his life couldn't ultimately be saved."
The incident will be investigated by the Indepedent Office for Police Conduct, she added.
Six-year-old Harry Jackson received the transplant at King's College Hospital in London and is believed to be one of only around 10 children worldwide to undergo the procedure.
Harry was born with malrotation, an abnormality of the bowel that occurs when the baby is developing in the womb.
He was at risk of volvulus, a potentially life-threatening complication of malrotation that occurs when the bowel twists, cutting off the blood supply to that part of the bowel.
Harry also developed intestinal failure-associated liver disease (IFALD), a progressive liver condition caused by years of receiving an intravenous form of feeding to manage his condition.
His parents, Annie Cerveno and Gary Jackson, met with the transplant team to discuss the possibility of a liver and bowel transplant and if they were a match.
The couple from Cambridge subsequently had tests, and, following weeks of assessments, Mr Jackson was confirmed to be a 98% human leukocyte antigen (HLA) match with Harry, meaning their immune systems were incredibly similar.
In January last year, Mr Jackson underwent the 17-hour operation at King's College Hospital to donate about 20% of his liver and 1.5m (4-5ft) of his small bowel to his son.
He said: "When you're a parent, you'd give your child anything in a heartbeat.
"So when I was told I could donate part of my liver and bowel to Harry, there was never a decision to make.
"I was just incredibly grateful that I had the opportunity to do something that could help save his life and give our little boy a second chance."
'The greatest privilege'
Mr Jackson, who had to lose six stone and give up alcohol prior to the operation, said the process had been "mentally and physically demanding" but insisted he would "do it all again without a second thought".
"Watching him recover and knowing that I had been able to play such a significant part in giving him that chance is something I'll never be able to put fully into words," Mr Jackson added.
"It remains the greatest privilege of my life."
Ms Cerveno admitted that they knew Harry would one day have to undergo a bowel transplant but hoped it would be "many years away".
However, she said that "everything changed" when his liver began to fail.
"As parents, you feel completely helpless watching your child wait for something so uncertain," Ms Cerveno said.
"The thought that one of us might be able to donate and give Harry that chance was something we wanted to explore immediately. If there was any possibility we could help him ourselves, we had to try."
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'Extremely rare' transplant
Currently, around three in 100 liver transplants performed in the UK are from living donors, with the majority of these for children.
Explaining the benefits of living organ donation, Ms Miriam Cortes-Cerisuelo, liver transplant consultant surgeon and clinical lead for transplant surgery at King's, said: "The donated organ is in excellent quality from a healthy donor, and the process allows better preparation and planning for the surgery.
"As a result, there are much better chances of success for the transplant.
"However, living donor transplants involving the small bowel and liver, such as the one that saved Harry's life, are extremely rare.
"There are around just 10 cases worldwide that we know of, all involving children."
Natalie McDonald, 34, and her niece Valentina Foster, seven, died in the blaze in Birchington Avenue, Grangetown, near Middlesbrough, on the morning of 26 August. Four other people were injured.
Cleveland Police said a 23-year-old man has been charged with two counts of murder, two counts of section 18 grievous bodily harm with intent and two counts of attempted section 18 grievous bodily harm with intent.
He is scheduled to appear at Teesside Magistrates' Court later on Tuesday.
Katie Smith, senior investigating officer from Northumbria Police, said: "This has been a truly tragic incident, and my thoughts remain with the families of all those involved.
"I would like to thank local residents for their support and patience during this complex investigation."
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Katie Nicolson, chief crown prosecutor for CPS North East, urged people to remember that legal proceedings are active and that the man has the right to a fair trial.
She added: "It is vital that there should be no reporting, commentary or sharing of information which could in any way prejudice these proceedings."
A 31-year-old man who was also arrested in connection with the case was released without charge on Sunday.
It is the first statement on the scandal that has split world football by lead investor Joshua Kushner, the brother of Trump's relative Jared Kushner and chief executive of Thrive Capital.
He was involved in secret talks with Mr Infantino about using his venture capital firm to sell off 20% of the World Cup to private investors before being forced to abandon the FIFA Forward Enterprise plans amid a global outcry led by Europe.
Mr Kushner said in a statement: "Money in football has historically been concentrated amongst a small group of countries.
"The idea behind FFE was to direct more capital and equity equally amongst all 211 member countries, providing significantly more investment to underdeveloped nations to nurture local talent, support grassroots football, enhance the fan experience, and ultimately grow the global game everywhere.
"It was an idea that every Member Association would vote on, not an obligation or determination. While we stand behind the motivations of FFE, we failed to appreciate the political dynamics of global football, and the lengths some would go to.
"Thrive has a long track record of being a partner to all constituents. Had we known what this would devolve into, we would not have gotten involved."
The statement was first published by US news site Axios and confirmed by Thrive to Sky News.
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UEFA has now asked a New York court to order Mr Kushner, who is not accused of wrongdoing, to hand over evidence linked to the venture as the European governing body pursues a potential criminal case against Mr Infantino in Switzerland.




