(NewsNation) — Nearly $1 billion in land purchases by a mysterious company near a California Air Force base is raising national security concerns.

A group called “Flannery Associates” has invested more than $800 million on almost 54,000 acres of land surrounding the Travis Air Force base since 2018, zoned for agricultural use, public records show.

Legal representation for Flannery says the group is controlled by U.S. citizens, with 97% of its capital coming from U.S.-based investors.

But after eight months of investigation, federal officials can’t confirm or deny this to be true and have not been able to determine exactly who is backing the company.

This so-called “mystery company” has been ramping up its purchases since the beginning of the year, prompting a federal investigation into its intentions. It is still unclear what Flannery’s purpose is for investing in land near the base.

The Air Force’s Foreign Investment Risk Review office is currently investigating Flannery Associates.

With so much mystery surrounding these purchases, some lawmakers say they are not ruling out the possibility of the group having ties to foreign enemies.

“We don’t know who Flannery is, and their extensive purchases do not make sense to anybody in the area,” California Rep. John Garamendi said, adding there are reasons to be concerned Flannery may have ties to China or other foreign enemies.

In a letter to the U.S. Department of Agriculture, Flannery Associates said: “No foreign person or group holds any significant interest of substantial control over Flannery, either now or at the time of any land purchase.”

This isn’t the only such land purchase near military bases that has raised concerns in recent months.

A few months ago, NewsNation looked into a now thwarted deal with Chinese-owned Fufeng Group in Grand Forks, North Dakota.

The purchase of 300 acres of farmland near the Grand Forks Air Force base raised flags about potential spying and was ultimately shut down after pushback from the community.

Another project is currently delayed in Green Charter Township, Michigan, following similar pushback on a proposed plant by Chinese electric vehicle battery maker Gotion.

Nearly 384,000 acres of agricultural land in the U.S. is controlled by China, and the rate at which they are purchasing land is growing exponentially, the USDA reports.

Chinese ownership of American farmland has increased 55% in the past five years, with almost 75% of it located in the South and about 16% on the West Coast.