In the remote, fog-shrouded valleys of southwest China's Sichuan Province, satellite imagery has exposed an intensifying nuclear buildup, signaling Beijing's preparations for heightened superpower tensions.

Nestled in the Zitong valley, engineers are constructing new bunkers and ramparts at a sprawling complex. The site features prominent pipes, indicating it processes highly hazardous materials, as observed in recent aerial views.

Nearby, the double-fenced Pingtong facility stands out as a suspected hub for producing plutonium-packed cores of nuclear warheads. Its centerpiece is a towering 360-foot-high ventilation stack, which has undergone recent refurbishments including new vents and heat dispersers. Additional construction is progressing adjacent to the main structure.

Prominently displayed above the Pingtong entrance, massive characters proclaiming a hallmark exhortation from China's leader Xi Jinping are visible even from space: “Stay true to the founding cause and always remember our mission.”

These developments at Zitong and Pingtong are part of a broader pattern among several secretive nuclear-related sites across Sichuan Province, which have seen expansions and upgrades in recent years.

The revelations come from satellite imagery captured by Airbus on February 2, highlighting China's accelerating nuclear infrastructure deep within its mountainous terrain.