Pentagon denied on Thursday media reports that a Russian nuclear powered submarine cruised unnoticed for several weeks in the Gulf of Mexico near the shores of the United States.

“I don't know what that information was based on, but it was not correct,” Wendy Snyder, a spokeswoman for the Pentagon, said.

The Washington Free Beacon reported earlier that Russia’s Akula class nuclear powered submarine (Project 971) freely traveled in June and July in the waters of the Gulf of Mexico undetected by the U.S. Navy.

A spokesman for the Russian Defense Ministry neither confirmed nor denied media reports on Thursday saying only that all information on the movement of Russian submarines around the world is classified.

The Akula is the main class of submarines employed by the Russian Navy. It has greater stealth capabilities than earlier models and is capable of carrying long-range ballistic missiles.