A new US bomb designed to hit Iran's underground nuclear sites has been spotted for the first time - but the images were quickly taken down amid security fears.
The US military posted pictures of a powerful bomb designed to penetrate deep into the earth and destroy underground facilities that could be used to enrich uranium.
Rare images of the weapon, the GBU-57, known as the "Massive Ordnance Penetrator" were posted on May 2 but were suddenly taken down.
