In an ongoing effort to identify possible safety defects, the US Air Force has grounded all 20 B-2 Spirit bombers until further notice, according to Air Force Times.

The decision to ground the whole fleet of nuclear bombers came after an emergency landing incident of a bomber on December 10 at Whiteman Air Force Base, Missouri which resulted from an unexplained in-flight problem, the report stated on Monday.

The Air Force decided to investigate the accident. Once the defect has been uncovered, the bombers will resume normal operations the report noted.

According to Air Force Times, 509th Bomb Wing spokesperson Master Sgt. Beth Del Vecchio said “Every incident is unique, and we are currently evaluating what went wrong and how we can mitigate future risk,” adding “We will resume normal operations once a safety investigation has been concluded.”

US unmasked high-tech B-21 stealth bomber

The Pentagon revealed early this month what it believes it can fight China with: the B-21 raider. 

Located at an Airforce facility in California, the raider is one of three weapon systems including silo-launched nuclear ballistic missiles and submarine-launched warheads, meant to advance warfare preparations against the "Chinese threat" keeping the US on its toes. 

In a statement, the Pentagon said of China's recent military  developments that they have birthed "the most consequential and systemic challenge to US national security and the free and open international system." 

Kathy Warden, Chair, CEO, and President of the aerospace and defense technology company Northrop Grumman commented: "With the B-21 the United States Air Force will deter and defeat threats anywhere in the world," adding: "The B-21 raider changes everything: reaffirming peace through deterrence, advancing technology, and ushering in a new paradigm in aircraft design, development, and manufacturing."

Read more: US military dwindling in strength: WSJ