At least one American citizen was shot dead and another injured by Cuban officials intercepting a speedboat off its coast on Wednesday, a US official has said, BBC reported. 

Border guards shot dead four people and injured the remaining six aboard the Florida-registered speedboat. Cuba accused the 10 people on the boat of planning "an infiltration with terrorist aims" and said they opened fire first.

A third person was on a US K-1 visa - for fiancées of American citizens - the US official said. The boat's owner alleged the vessel had been stolen by an employee, according to BBC.