China carried out a long-range missile flight test on Saturday using multiple, independently targetable reentry vehicles, or MIRVs, according to U.S. defense officials.

The flight test Saturday of a new DF-41 missile, China’s longest-range intercontinental ballistic missile, marks the first test of multiple warhead capabilities for China, officials told the Washington Free Beacon.

China has been known to be developing multiple-warhead technology, which it obtained from the United States illegally in the 1990s.

However, the Dec. 13 DF-41 flight test, using an unknown number of inert maneuvering warheads, is being viewed by U.S. intelligence agencies as a significant advance for China’s strategic nuclear forces and part of a build-up that is likely to affect the strategic balance of forces.

China’s nuclear arsenal is estimated to include around 240 very large warheads. That number is expected to increase sharply as the Chinese deploy new multiple-warhead missiles.

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