A major vulnerability that allowed French submarine to “sink” aircraft carrier USS Theodore Roosevelt and most of its escort during drills was apparently revealed by the French Navy and Defense Ministry in blogposts that were quickly wiped out.

Both the French Defense Ministry and the Navy released and then quickly deleted a news post entitled “Le SNA Saphir en entraînement avec l’US Navy au large de la Floride” (“The SNA Sapphire in training with the US Navy off the coast of Florida”) that praised the 34-year-old French nuclear submarine’s success in “sinking” the American aircraft carrier USS Theodore Roosevelt along with best part of its escort.

The news, before it was deleted was spotted by several outlets, including The Aviationist blog, which disclosed the information which the French authorities initially shared.

The aim of the military games off the coast of Florida which began in mid-February were meant to test the newly upgraded carrier, which had undergone a four year, $2.6 billion overhaul, ahead of the Strike Group's deployment. The drills involved practicing scenarios of hostile ship boarding, submarine attacks, and enemy ships battles.

The service conducts “full-ship shock trials” the USS Roosevelt http://t.co/z8zBaEZt2Apic.twitter.com/VJCawndfjQ — Brian Dreyer (@Bwdreyer) January 19, 2015

During the first phase of the 10 days naval exercises, the French Saphir sub was part of the so-called friendly force to support anti-submarine warfare.

However, in the second phase of the games, the Saphir turned foe and was integrated with the imaginary enemy forces. Its mission become to locate Theodore Roosevelt and to prepare an attack on the strike group by guiding the ships.

During that last stage of the drills, the French sub snuck up undetected on US Carrier Strike Group 12 by penetrating a US defensive screen.

“The Saphir has quietly slipped into the heart of the screen formed by the American frigates protecting the aircraft carrier, while avoiding detection against-pervasive air assets ,” the original release read as quoted by French Challenges blog. “On the morning of the last day, the order of fire was finally given, allowing the Saphir to fictitiously sink Theodore Roosevelt and most of its escort.”

No other details are available about the outcome of the exercise. The strike group will be deployed later this year to provide an overseas forward presence and maintain US maritime security abroad.