A Silicon Valley engineer who tweeted an offer to sell ventilators to President Trump and then received $69 million from New York for a contract he never fulfilled also apparently attempted to sell large quantities of N95 masks to California.

The man, Yaron Oren-Pines, proposed selling the state at least 18 million of the masks in late March as concerns about a shortage of personal protective equipment to fight the coronavirus pandemic mounted, BuzzFeed News has learned.

In that instance, Oren-Pines turned to a different social media platform: Nextdoor, a hyperlocal site that’s typically used to alert neighbors of prowlers, sell used furniture, or advertise babysitting gigs.

“3M 1860 N-95 Masks - Very large quantities for Government - please help,” an account in the name of Yaron Oren-Pines posted to the Nextdoor site in the San Jose area on March 21. “Those are the masks that everyone (in the world) is searching for.”

A spokesperson for the California Department of Public Health said the agency has not made any purchases from Oren-Pines or his companies. Agency officials did not provide detail on whether they had any contact with him.

Oren-Pines did not immediately respond to a request for comment on the masks. In a brief phone conversation last week about ventilators, Oren-Pines said, “Neither me nor my company is providing any comment on this,” before hanging up. Since then, Oren-Pines’ Twitter account, which had only 75 followers as recently as last Wednesday, has been deleted.

Fellow Nextdoor users immediately dismissed his mask offer as less than credible. “Scam,” wrote one user. “No regular business around here is going to have ‘millions” of masks.”

Something very different happened six days later when Oren-Pines made a similar offer on Twitter, this time for ventilators.

Replying to a March 27 tweet by President Trump calling for ventilators, the engineer wrote, “We can supply ICU Ventilators, invasive and noninvasive. Have someone call me URGENT.”

On March 30, New York’s Department of Health paid him $69.1 million for 1,450 ventilators that, in the end, he never delivered. That came out to more than $47,000 for each ventilator, or three times the market price for many such units. According to a New York State official, Oren-Pines was referred to Albany directly by the White House Coronavirus Task Force.

A report by the New York Times on Tuesday found that Oren-Pines had been referred by members of a team overseen by Jared Kushner to the Department of Health and Human Services, which in turn forwarded the referral to Gov. Andrew Cuomo’s office. Because the recommendation came from the administration, New York officials, according to that report, assumed Oren-Pines had been properly vetted and cut the check almost immediately.

New York has been able to recover $59.1 million of the payment, according to Richard Azzopardi, a senior adviser to the governor. The state is still hoping to get a smaller number of ventilators or a refund of the remaining $10 million, he added.

Oren-Pines, an electrical engineer with numerous patents in mobile networking technology, has no apparent experience in ventilators, respirator masks, or other medical devices. He is a founder of several companies related to the cellular phone industry, but none have any public record of government contracting.

N95 masks, which are designed to filter out 95% of particles smaller than 0.3 microns in diameter, are a critical piece of personal protective equipment for combating coronavirus. A combination of soaring global demand and massive supply-chain disruption has sharply driven up prices of the masks. California’s Department of Transportation, for example, last month paid $12.74 apiece for masks made by US manufacturer 3M.

That’s more than 10 times the price of $1.27 that 3M asks its distributors to charge for its 1860 mask, which is rated for surgical use. In recent weeks, 3M has filed at least eight federal lawsuits against companies that attempted to sell its masks at inflated prices, often to government agencies. The companies, 3M has alleged, were not authorized distributors and violated its trademarks, as well as state-level anti–price gouging laws.

“Unfortunately, any number of wrongdoers seek to exploit the current public health emergency and prey on innocent parties through a variety of scams,” 3M wrote in several of the complaints it filed. “These scams include unlawful price gouging, fake offers, counterfeiting, and other unfair and deceptive practices - all of which undercut the integrity of the marketplace and constitute an ongoing threat to public health and safety.”

None of the lawsuits, to date, have been directed at Oren-Pines. However, his post on Nextdoor did attract some skepticism.

“How does this guy have so many masks, and he doesn't know what to do with them,” San Jose resident Linda York recalled thinking when she saw the post. “Like, why would he post on Next Door?”

After spotting it, she reported the post to the “Neighborhood Lead,” who is responsible for moderating content in the Graystone Nextdoor site. Oren-Pines lives in a nearby San Jose neighborhood and posted in a number of the surrounding areas. In her message, she voiced concerns that Oren-Pines was “trolling everyone, and is fraudulent in bringing hope to the hospital community.”

Screenshots from the group obtained by BuzzFeed News and dated March 21 show that several in the group were concerned about the legitimacy of the mask supply.

“Who is Yaron Oren-Pines from Almaden Meadows who has 18 million N95 masks???” wrote one commenter. “People’s lives are on the line. I’m shocked.”

The post was removed from the site, but it is unclear if Oren-Pines removed it himself. Nextdoor did not immediately respond to a request for comment.

When Oren-Pines made headlines for his $69 million contract last week, York said she saw the story but didn’t realize it was about the same man who had posted in their neighborhood group just a couple of weeks ago. She and others in the group were shocked that New York state had already paid him $69 million for ventilators.

“Our Nextdoor group was more savvy than the White House,” said York. “We all figured he was a scam artist. We vetted him instantaneously.”