Police said they were called to reports of a "large sign" falling at the Big Church Festival at Wiston Park, near Steyning, on Friday afternoon.
A 41-year-old man from Eastbourne was pronounced dead at the scene. His next of kin have been informed.
Detective Chief Superintendent Richard McDonagh said at least six other people had been taken to hospital.
Festival-goers were initially told Friday's show had been cancelled, before organisers confirmed the whole festival had been brought "to a close". It had been due to end on Sunday.
A festival spokesperson said on social media: "We are devastated by the serious incident that took place at Big Church Festival 2026 today, in which a sign fell, injuring at least seven people, one of whom tragically lost their life.
"First and foremost, all of our thoughts are with those who have been affected, their families and friends, and everyone who witnessed what happened."
Police were still at the scene on Friday night and the incident has been reported to the Health and Safety Executive and the local authority.
Anyone with relevant video footage is asked to call 101 and quote Operation Igloo, or visit the Sussex Police website.
Big Church Festival was founded in 2009 and organisers say it is the UK's biggest Christian festival.
Winds of up to 27mph were recorded about five miles away in Shoreham on Friday, according to the Met Office.
The executives, who asked not to be named, also noted that while casting the duchess might generate interest, it would also be "risky".
Harry and Meghan landed in the UK this week - just days after announcing they would relocate to the country with their children Archie and Lilibet.
The couple stepped back from royal duties in 2020 and went to live in California.
The surprise announcement sparked speculation - and the duchess was said to have had talks about a role in season three of Guy Ritchie's Netflix hit, The Gentlemen.
One producer who has worked with Netflix told us: "You don't uproot your family for one role in a show."
They added: "There's no chance the reason they're coming back is TV roles like The Gentlemen."
As for whether Meghan could join the cast of the show, they added: "I think the producers have said, 'There's a part for two episodes, let's look into that' - but then decided, 'reverse, reverse, the publicity is terrible'.
"I doubt the producers or Netflix are enjoying this kind of attention."
Another told us that if she was cast, "I don't think people would stop watching because she is in it. They have a fanbase already and there is the possibility that Meghan could add some audience."
The insiders agree the duchess would "attract publicity", which could generate "higher ratings" for shows.
But casting her would come with its own set of problems, too, the industry insiders have told us.
"You need actors who inhabit roles and are believable. How do you get over the fact she's a duchess?" said one.
"I don't think Meghan would get a project greenlit just with her attached because, despite her being quite famous, it's quite an unknown, and she is divisive."
Since the Sussexes left their lives as full-time working royals, their popularity in the UK has plummeted.
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There are practical issues too, "imagine the security we would need on set," said another TV insider.
When she married Prince Harry in 2018, Meghan ended her acting career to focus on her charitable causes and royal duties.
She rose to fame on the screen playing paralegal Rachel Zane in the show Suits for seven series.
Together, Harry and Meghan signed multi-million-pound deals with Spotify for a podcast series and with Netflix for programmes including the duchess's lifestyle show With Love, Meghan.
Their podcast deal ended, and Meghan's Netflix show was not renewed for a third season, but it's reported that the Sussexes remain on a downgraded first-look deal with the streaming giant.
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And the couple were executive producers on the documentary Cookie Queens, which was released in January.
There is little precedent for women who marry into the Royal Family returning to their careers.
When Sophie, the Duchess of Edinburgh, married Prince Edward, she gave up her job working in PR.
"It will be hard for Meghan to find the right roles. She's had success, and she's a good actress," another executive said.
"But she's not Grace Kelly, who was a world-famous actress who became a princess."
The US president provided few details about the agreement, saying only that the US had secured majority control of more than 65 billion barrels of Venezuela's proven oil reserves through a partnership with private business.
The new deal represents a dramatic expansion of the US role in Venezuela's oil industry.
In a post on his Truth Social platform, Mr Trump said the deal had been negotiated by secretary of state Marco Rubio, defence secretary Pete Hegseth and Venezuela's interim president Delcy Rodriguez.
"At my direction, Secretary of State Marco Rubio, and Secretary of War Pete Hegseth, working closely with Highly Respected Interim President of Venezuela, Delcy Rodriguez, and, through a partnership with private business, have secured majority U.S. control of more than 65 BILLION BARRELS of proven Oil Reserves in Venezuela, at no cost to the American Taxpayer," Mr Trump said.
Mr Trump added that the transaction "MORE THAN DOUBLES American Oil Reserves".
Mr Rubio said the agreement would usher in billions in private investment into Venezuela and lead to lower gas prices in the US.
"This deal is a huge win for both the American and Venezuelan people," he wrote on X.
Ms Rodriguez also welcomed the agreement, saying it would boost the Venezuelan economy and "have a significant impact on our nation's revival".
Her government said in a statement that the deal involves the development of 17 fields with a proven potential of 65 billion barrels.
It said the agreement could draw $100bn in investment into Venezuela's oil industry and yield over $209bn in taxes for Caracas.
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The announcement comes almost nine months after the US military carried out an operation to capture Venezuela's then president Nicolas Maduro to face federal narcoterrorism and drug trafficking charges in the US.
Mr Trump is facing increasing pressure as the US midterm elections loom, and gas prices have spiked because of the war with Iran, which the US and Israel started six months ago.
Venezuela has one of the largest oil reserves in the world, amounting to about 17% of the world's supply, according to the US Energy Information Administration.
Unlike other parts of the world, where geologists have to search for untapped oil, the reserves under Venezuela's soil are largely mapped and known - but because of dilapidated infrastructure, the country only produces about 1% of the world's oil.
The force, investigating a series of recent incidents in the Middlesbrough area, said a total of 24 people had now been arrested.
It comes after reports emerged that several cars were set on fire at a vigil in neighbouring County Durham to remember 23-year-old Michael Cahill - one of five young men in a stolen car driving down the wrong side of the A66 on Saturday.
The Volkswagen Passat collided with a police car, killing all seven, including PCs Tom Clough and Matthew Blades.
In an update on their investigation in the area since that incident, Cleveland Police said that they had arrested four men on suspicion of criminal damage with intent to endanger life, arson and possession with intent to supply class A drugs.
The force said all four - aged 35, 25, 40 and 21 - were in a vehicle when they were stopped by police on Kingsley Road in Grangetown at 10.30pm on Thursday.
It added that the arson relates to a caravan that was set alight on Atlee Road on Wednesday, while the criminal damage with intent to endanger life relates to a vehicle crashing into a property at Steele Crescent.
Three others arrested and £15,000 seized
The force also said a further three - aged 23, 42 and 30 - had been arrested.
The 23-year-old was arrested on suspicion of threats to kill.
Officers added that the 42-year-old man was arrested on suspicion of threats to kill and possession of criminal property, while the 30-year-old was arrested on suspicion of possession of criminal property.
All three have been released on conditional bail, police said, adding officers also seized £15,000 in cash.
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Social media videos on Thursday appeared to show vehicles alight in Haswell, County Durham, where balloons, flares and fireworks were released in tribute to Cahill.
Other footage seemed to show burnt-out cars being moved from the field, 20 miles north of the crash site, by a tractor.
Durham Constabulary said they were called to a private field soon after 5.30pm on Thursday, where five vehicles were wrecked as a large crowd gathered.
The crowd's behaviour was condemned as "completely unacceptable" by officers who said it was deemed safest to let the vehicles burn out.
Nobody was injured, and there were no arrests.
Two arrested for murder after house fire
Labour MP for Middlesbrough and Thornaby East Andy McDonald described the spate of violence in the Middlesbrough area as "terrorism".
It comes as more than 200 extra officers have been drafted in to help Cleveland Police after multiple violent incidents across Middlesbrough.
Meanwhile, two men have been arrested on suspicion of murder in relation to the house fire that killed Natalie McDonald, 34, and her niece Valentina Foster, and injured four others.
A woman and a seven-year-old girl died in a house fire in Grangetown, near Middlesbrough, on Wednesday - just one mile away from where two police officers and five young men were killed in the head-on car crash on the A66 in South Bank early on Saturday.
Police said on Friday afternoon that they are not linking the house fire with the A66 crash.
Yiannopoulos was arrested at Louis Armstrong New Orleans International Airport and accused him of overstaying after entering the US legally in May 2019 through New York City
An immigration judge issued a final order of removal on 22 July after Yiannopoulos failed to show up for his immigration hearing, a DHS spokesperson wrote in an email to AP news agency.
"He chose to overstay his welcome in violation of our nation's laws," a spokesperson for DHS wrote in an emailed statement.
ICE's online detainee locator does not say where Yiannopoulos is being held but directs family and legal representatives to the agency's office in Alexandria, Louisiana, a deportation hub for international flights.
Representatives of Yiannopoulos did not respond to AP's request for comment.
It is unclear whether he has legal representation.
Who is Milo Yiannopoulos?
Yiannopoulos is a well-known champion of conservative causes and has frequently taken provocative public positions on feminism, Islam and immigration.
He has been especially supportive of President Donald Trump's immigration crackdown.
"Zero immigration for the next 20 years. No ifs, no buts," Yiannopoulos wrote on the social platform X last year - despite his own apparent immigration status.
Yiannopoulos rose to fame in the early 2010s as an incendiary writer for the conservative website Breitbart News.
He resigned from the company in 2017 after a video of him endorsing paedophilia resurfaced online.
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He later apologised for the remarks and said he himself was a victim of sexual assault as a minor.
Far-right conservative activist Laura Loomer, who Yiannopoulos has publicly feuded with for years, swiftly took to social media to applaud his arrest.
In 2022, he was an intern for former Congresswoman Marjorie Taylor Greene, according to the Washington Post.
He subsequently ran the short-lived 2024 presidential campaign for controversial rapper Kanye West, who now calls himself Ye.
Most recently, Yiannopoulos worked as a spokesperson for Ye, who has been beset by controversy of his own following antisemitic comments that the rapper has since apologised for.