Almost 600 people have signed an open letter to leaders at venture firm Sequoia Capital after one of its partners, Shaun Maguire, posted what the group described as a “deliberate, inflammatory attack” against the Muslim Democratic mayoral candidate in New York City.

Maguire, a vocal supporter of President Donald Trump, posted on X over the weekend that Zohran Mamdani, who won the Democratic primary last month, “comes from a culture that lies about everything” and is out to advance “his Islamist agenda.”

The post had 5.3 million views as of Monday afternoon. Maguire, whose investments include Elon Musk’s SpaceX and X as well as artificial intelligence startup Safe Superintelligence, also published a video on X explaining the remark.

Those signing the letter are asking Sequoia to condemn Maguire’s comments and apologize to Mamdani and Muslim founders. They also want the firm to authorize an independent investigation of Maguire’s behavior in the past two years and post “a zero-tolerance policy on hate speech and religious bigotry.”

They are asking the firm for a public response by July 14, or “we will proceed with broader public disclosure, media outreach and mobilizing our networks to ensure accountability,” the letter says.

Sequoia declined to comment. Maguire didn’t respond to a request for comment, but wrote in a post about the letter on Wednesday that, “You can try everything you want to silence me, but it will just embolden me.”

Among the signees are Mudassir Sheikha, CEO of ride-hailing service Careem, and Amr Awadallah, CEO of AI startup Vectara. Also on the list is Abubakar Abid, who works in machine learning Hugging Face, which is backed by Sequoia, and Ahmed Sabbah, CEO of Telda, a financial technology startup that Sequoia first invested in four years ago.

At least three founders of startups that have gone through startup accelerator program Y Combinator added their names to the letter.

Sequoia as a firm is no stranger to politics. Doug Leone, who led the firm until 2022 and remains a partner, is a longtime Republican donor, who supported Trump in the 2024 election. Following Trump’s victory in November, Leone posted on X, “To all Trump voters:  you no longer have to hide in the shadows…..you’re the majority!!”

By contrast, Leone’s predecessor, Mike Moritz, is a Democratic megadonor, who criticized Trump and, in August, slammed his colleagues in the tech industry for lining up behind the Republican nominee. In a Financial Times opinion piece, Moritz wrote Trump’s tech supporters were “making a big mistake.”

“I doubt whether any of them would want him as part of an investment syndicate that they organised,” wrote Moritz, who stepped down from Sequoia in 2023, over a decade after giving up a management role at the firm. “Why then do they dismiss his recent criminal conviction as nothing more than a politically inspired witch-hunt over a simple book-keeping error?”

Neither Leone nor Moritz returned messages seeking comment.

Roelof Botha, Sequoia’s current lead partner, has taken a more neutral stance. Botha said at an event last July that Sequoia as a partnership doesn’t “take a political point of view,” adding that he’s “not a registered member of either party.” Boelof said he’s “proud of the fact that we’ve enabled many of our partners to express their respected individual views along the way, and given them that freedom.”

Maguire has long been open with his political views. He said on X last year that he had “just donated $300k to President Trump.”

Mamdani, a self-described democratic socialist, has gained the ire of many people in tech and in the business community more broadly since defeating former New York Gov. Andrew Cuomo in the June primary.

— CNBC’s Ari Levy contributed to this report.

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Sophisticated drones sending “overwhelming amounts” of drugs and weapons into prisons represent a threat to national security, according to an annual inspection report by the prisons watchdog.

HMP chief inspector of prisons Charlie Taylor has warned criminal gangs are targeting jails and making huge profits selling contraband to a “vulnerable and bored” prison population.

The watchdog boss reiterated his concerns about drones making regular deliveries to two Category A jails, HMP Long Lartin and HMP Manchester, which hold “the most dangerous men in the country”, including terrorists.

Mr Taylor said “the police and prison service have in effect ceded the airspace” above these two high-security prisons, which he said was compromising the “safety of staff, prisoners, and ultimately that of the public”.

“The possibility now whereby we’re seeing packages of up to 10kg brought in by serious organised crime means that in some prisons there is now a menu of drugs available,” he said. “Anything from steroids to cannabis, to things like spice and cocaine.”

“Drone technology is moving fast… there is a level of risk that’s posed by drones that I think is different from what we’ve seen in the past,” warned the chief inspector – who also said there’s a “theoretical risk” that a prisoner could escape by being carried out of a jail by a drone.

He urged the prison service to “get a grip” of the issue, stating: “We’d like to see the government, security services, coming together, using technology, using intelligence, so that this risk doesn’t materialise.”

The report makes clear that physical security – such as netting, windows and CCTV – is “inadequate” in some jails, including Manchester, with “inexperienced staff” being “manipulated”.

Mr Taylor said there are “basic” measures which could help prevent the use of drones, such as mowing the lawn, “so we don’t get packages disguised as things like astro turf”.

Responding to the report, the Prison Advice and Care Trust (PACT) said: “The ready access to drugs is deeply worrying and is undermining efforts to create places of rehabilitation.”

Mr Taylor’s report found that overcrowding continues to be what he described as a “major issue”, with increasing levels of violence against staff and between prisoners, combined with a lack of purposeful activity.

Some 20% of adult men responding to prisoner surveys said they felt unsafe at the time of the inspection, increasing to 30% in the high security estate.

Andrea Coomber, chief executive of the Howard League for Penal Reform, said: “This report is a checklist for all the reasons the government must prioritise reducing prison numbers, urgently.

“Sentencing reform is essential, and sensible steps to reduce the prison population would save lives.”

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The report comes after the government pledged to accept most of the recommendations proposed in the independent review of sentencing policy, with the aim of freeing up around 9,500 spaces.

Those measures won’t come into effect until spring 2026.

Prisons Minister Lord Timpson said Mr Taylor’s findings show “the scale of the crisis” the government “inherited”, with “prisons dangerously full, rife with drugs and violence”.

He said: “After just 500 prison places added in 14 years, we’re building 14,000 extra – with 2,400 already delivered – and reforming sentencing to ensure we never run out of space again.

“We’re also investing £40m to bolster security, alongside stepping up cooperation with police to combat drones and stop the contraband which fuels violence behind bars.”