Joe Rogan has called out speculation that Meta CEO Mark Zuckerberg has built a nuclear bunker to shield himself should such a war break out.

Amid international tensions over the past few decades, there have often been unverified reports of public figures having built nuclear bunkers in the hopes they would be kept safe should there ever be a nuclear strike.

Rogan said that Zuckerberg was one such figure when he spoke on his podcast last week with investigative journalist Annie Jacobsen. In her latest book, Nuclear War: A Scenario, Jacobsen interviewed a number of defense officials.

Jacobsen said that, from the information she gathered, the scenario of a nuclear war “doesn’t end well. Not only does it not end well, 5 billion people are dead at the end of 72 minutes.”

The writer went on to tell Rogan that “if nuclear war begins, it doesn’t end until there is a nuclear holocaust. And it happens so fast—there is no quickly going to your secret bunker you have.”

“Yeah, all that’s nonsense,” Rogan said. “These people think, like, Zuckerberg is building a bunker in Hawaii [and] he’s going to survive. He’s building a hurricane shelter that might not work.”

Jacobsen said: “And also, unless he happened to be there in the exact moment when all of this went down…”

“Yeah, you’d have to know in advance that we’re about to launch,” Rogan said, adding that “the whole thing is terrifying.”

In December, Wired published a report that said Zuckerberg and his wife, Priscilla Chan, are planning to building an underground shelter measuring 5,000-square-foot on their Hawaii ranch. The shelter would have its own energy and food supplies.

Sitting on the couple’s 1,400-acre compound on the island of Kauai, Ko’olau Ranch’s planning documents were pored over by Wired. The outlet said the ranch will include more than a dozen buildings with at least 30 bedrooms and 30 bathrooms, as well as two mansions and 11 tree houses.

At the time the investigative article was published, it was not made clear what the bunker’s intended use was. Brandi Hoffine Barr, a spokesperson for Zuckerberg and Chan, told Time magazine that Kauai County encourages homeowners to build shelters. Over the past two decades, the county has offered tax breaks to residents who construct hurricane-resistant safe rooms.

“Mark and Priscilla value the time their family spends at Ko’olau Ranch and in the local community, and are committed to preserving the ranch’s natural beauty,” Hoffine Barr told Time in a statement.

Per the statement, there were plans to build 80 luxury homes on the property before the couple purchased it. They are now developing on less than one percent of that land, said the spokesperson, who added that the remainder would be used for farming, ranching, conservation, and wildlife preservation.

Data from the Federation of American Scientists shows Russia currently owns the most nuclear warheads in the world, with 5,977, while the U.S. has 5,428. The Federation of American Scientists also said that “of the world’s 12,700 nuclear warheads, more than 9,400 are in the military stockpiles for use by missiles, aircraft, ships and submarines.”