CLAIM: U.S. Nuclear-Powered Submarine Slipped Into Port Harcourt Waters Unannounced
A Facebook account, @INews claims that a U.S. nuclear-powered submarine “slipped into Port Harcourt waters” without notification, carrying “heavy strategic weapons. The post which was shared on November 16, 2025 had an image of a submarine and President Trump and Tinubu with a caption that said according to military insiders, the vessel entered Nigerian territorial waters under the cover of darkness, without prior notification to the Nigerian Navy.
The post also quoted a security anonymous source who was alleged to have said that “the firepower on that submarine can turn a nation into dust within minutes.”
VERIFICATION
A fact-check of the attached pictures shows that the first Submarine is an image of the ARA San Juan (S-42), a TR-1700-class diesel-electric submarine that was in service with the Argentine Navy. It disappeared in November 2017 off the East coast of Argentina and its wreck was later found.
The second submarine is confirmed to be the USS Connecticut (SSN-22), a Seawolf-class fast-attack submarine of the United States Navy. The Seawolf-class submarines are highly advanced and were designed for deep-ocean surveillance and anti-submarine warfare. Only three submarines of this class were built due to their high cost. In October 2021, the USS Connecticut was involved in an incident where it struck an uncharted seamount while submerged in the Indo-Pacific region, causing significant damage to its bow.
The ARA San Juan (S-42) is not currently in operation; it was lost at sea after an implosion on November 15, 2017, which resulted in the deaths of all 44 crew members. The wreckage of the submarine was found in November 2018 at a depth of approximately 907 meters (97 meters).
USS Connecticut (SSN-22) is currently in dry dock four years after its October 2021 collision with an uncharted seamount in the South China Sea. The incident, which caused severe damage and led to the firing of its command team, has left the submarine in a lengthy and complex repair process at Puget Sound Naval Shipyard; this renders it immobile and inoperable.
Maritime law, especially UNCLOS, allows submarines to operate freely in international waters and a foreign state’s exclusive economic zone, but it places strict limits on what they can do inside another country’s territorial waters. A submarine is not allowed to enter territorial waters while submerged and must remain on the surface and show its flag if it is making an innocent passage. Covert operations, intelligence gathering, or any activity that threatens the security of the coastal state inside that 12-mile zone are considered violations of sovereignty.
However, Nigeria does not currently operate its own submarines and has been reported as having missed out on the global race for submarines. Publicly stated priorities of the Nigerian Navy revolve around maritime crime, piracy, and economic security. There is also renewed effort to strengthen maritime domain awareness through fleet modernisation. The Nigerian Navy has made public statements about boosting maritime security and modernising its fleet, including commissioning three warships and several helicopters.
Meanwhile, there is no publicly available from the Navy press or ministry of defence release or official communication admitting to detecting or detaining a foreign submarine. Mentions of handling nuclear submarine threats have not appeared in public statements by senior Nigerian government officials or naval leadership. Further checks on US government press releases reveal no mention of submarines deployed to Nigeria.
CONCLUSION
The claim that a United States nuclear-powered submarine secretly entered Port Harcourt waters is FALSE. There are no confirmations from the Nigerian Navy, no statements from the U.S. government, and no reports from reputable media organisations.
