According to report, the security of the U. S. government plant for storing weapons-grade uranium was unable to prevent activists from entering the plant before surrendering to the authorities.

Several activists including an 82-year-old nun cut the fences of the storing facility and later walked to officer's car and offered to surrender. A new report by the Energy Department's inspector general, Gregory Friedman offered criticism for several failures of the sophisticated security systems.

The report also criticizes show of ineptitude by the security personnel at the Y-12 facility in Oak Ridge, Tennessee during the month of July 2012. A total of three anti-nuclear activists entered the fence without being spotted by the security present at the plant on 28 July.

They vandalized a building that was termed as a facility with high security cover. The building holds largest inventories of nuclear material in the world, according to experts. It is believed that senior officials from the Energy Department will face scrutiny over the serious breach of security at the critical facility.

The facility is run by Babcock & Wilcox Co and it is responsible for the security provided by WSI Oak Ridge, provider.