As arms agreements fray, China secretly expands its nuclear weapons infrastructure

When three villagers from China’s Sichuan province wrote to local officials in 2022 asking why the government was confiscating their land and evicting them from their homes, they received a terse reply: It was a “state secret.”

That secret, a CNN investigation has found, centered on China’s covert plans to massively expand its nuclear ambitions.

More than three years after the evictions, satellite images show, their village has been flattened and, in its place, new buildings erected to support some of China’s most important nuclear weapons production facilities.

The expansion of the sites in Sichuan province, observed in satellite imagery and a review of dozens of Chinese government documents, supports recent claims by the administration of US President Donald Trump that Beijing has been conducting its most significant nuclear weapon modernization campaign in decades.

Trump is set to visit Beijing on a landmark trip next month where he is expected to try to begin a dialogue about a deal to curb Chinese leader Xi Jinping’s nuclear ambitions. Earlier this year, the latest arms reduction agreement between Russia and the United States – known as New START – expired, with Trump wanting to strike a new and improved deal with Moscow that would also include China.

But the dramatic changes seen at sites in Sichuan suggest that the nuclear weapons development of China’s military, known as the People’s Liberation Army (PLA), shows little sign of abating.

One of the most substantial additions to the area is an enormous dome, unusually shaped like a Tic Tac, emerging from the banks of the Tongjiang River in less than five years. It appears to continue to be outfitted with equipment, suggesting it may not yet be in use.

At 36,000 square feet – the size of 13 tennis courts – the reinforced dome is enclosed by a concrete and steel structure with radiation monitors and blast doors, its network of pipes snaking out of the facility and into a building with a tall ventilation stack. These and other features, including extensive air handling equipment, are designed to keep highly radioactive materials such as uranium and plutonium trapped inside the dome, according to multiple experts.

The facility, which was built inside a nuclear weapons base long known to the CIA, is encircled by three layers of security fencing. A nearby tunnel disappears into the side of a mountain. To analyze individual features of the site known as 906, CNN compiled more than 50 snapshots from different phases of the facility’s construction into a 3D model.