Russia recorded SOS signals from a foreign submarine when its own nuclear submarine, the Kursk, was sinking with 118 sailors on board in August, a top navy commander reportedly has said. The cause of the accident with the Kursk in the Barents Sea remains unclear but Russian officials have said a collision was a possibility. The United States and Britain have denied their submarines were involved. Northern Fleet commander Vyacheslav Popov told the newspaper Nezavisimaya Gazeta there was growing evidence the Kursk sank after a collision with a foreign vessel. "The 'Polinom' hydro-acoustic system located SOS signals sent by a mechanical transmitter," Popov said, referring to Russian naval surveillance equipment.