American citizen among dead in Cuba speedboat interception

US officials say at least one American citizen was killed and another injured when Cuban border guards intercepted a Florida-registered speedboat off Cuba; four people on the boat were killed and six were wounded in the firefight. Cuba claims the passengers, Cuban nationals in the US, planned an armed infiltration and opened fire first, while the boat owner says it was stolen. An 11th person was reportedly arrested; the US says no American government personnel were involved, and the incident adds to ongoing US-Cuba tensions.