Two nuclear-armed submarines are said to have collided in the Atlantic Ocean. The British and French boats were on separate missions when the incident is said to have happened earlier this month. Britain’s Ministry of Defence has declined to comment, while Paris admitted its boat had hit something, but not a British sub.HMS Vanguard is said to have dents and scrapes on its hull. France’s Le Triomphant reportedly suffered damage to its sonar dome. Experts said modern anti-sonar technology is so effective that neither boat may have known the other was there. HMS Vanguard is one of four British boats carrying Trident nuclear missiles. Le Triomphant is part of a similar four-strong French nuclear fleet.