Mark Zuckerberg’s huge, secretive compound on the Hawaiian island of Kauai partially sits atop a family burial site previously owned by a native Hawaiian who is raising concerns that remains of other family members on the grounds may be bulldozed over as the Meta CEO expands his land grab.

Mr. Zuckerberg’s $300 million compound sits on land Julian Ako’s family formerly owned, Wired reports. Mr. Ako’s great-grandmother and her brother are buried on the land and other relatives could be buried there.

Mr. Ako was able to go onto the property and identify the graves but it took months of discussions with a representative of Mr. Zuckerberg, according to the report. He wasn’t able to locate remains of other ancestors but worries what could happen if other burial sites are found on the property.

As is common with projects for billionaires, its many construction workers are under nondisclosure agreements that forbid them from disclosing anything about what they are doing.

“If all of the workers have signed these nondisclosure agreements, then basically they’re sworn to silence,” Mr. Ako tells Wired. “If they uncover iwi — or bones — it’s going to be a challenge for that to ever become public knowledge, because they’re putting their jobs in jeopardy.”

A representative for  Mr. Zuckerberg, Brandi Hoffine Barr, says the known family burial plot is fenced off and maintained. She also says if any other remains are found they are legally required to report them.

Mr. Zuckerberg’s sprawling main property has been the source of rumors over the years, including reports that it contains a deeply-buried doomsday bunker with blast-proof doors. Mr. Zuckerberg has disputed that description, saying on a podcast earlier this year that it is a tunnel to a storage room. Last year he suggested it could be used as a hurricane shelter.

Hawaii News Now reports that planning documents filed with the county show a nearly 4,500 square foot underground “storm shelter” on the property.

Mr. Zuckerberg is one of the biggest landowners in Hawaii and his property is expanding. He made his first land purchases in 2014 — a 357-acre former sugarcane farm and a majority stake in a 393 acres at Pia’a Beach, where the compound is being built. The properties combined cost $116 million, according to the Robb Report.

He has continued to gobble up more Kauai land, including 89 acres in 2017 and nearly 600 acres in 2021.

Now Wired says Mr. Zuckerberg has purchased another 962 acres of ranchland across the road from his compound under an LLC. In all, that’s more than 2,300 acres on the island.

He is building guest housing for family, friends, and staff on the new land, Ms. Hoffine Barr says. The ranch could also be used to raise cattle, which Mr. Zuckerberg announced in 2023 that he was planning to do.

“Mark and Priscilla continue to make a home for their family and grow their ranching, farming, and conservation efforts at Ko’olau Ranch,” Ms. Hoffine Barr says. “The vast majority of the land is dedicated to agriculture—including cattle ranching, organic ginger, macadamia nut, and turmeric farming, native plant restoration, and endangered species protection.”