Four people aboard a speedboat registered in Florida are dead after a shootout with Cuban troops in Cuban territorial waters ... according to Cuba's government.

The deadly shootout happened Wednesday morning near an island in Cuba's Villa Clara province on the country's northern coast ... according to a statement from Cuba's Ministry of the Interior.

Cuba says people onboard the Florida-registered speedboat opened fire against a Cuban coast guard vessel that approached them ... the commander of the Cuban vessel was injured by gunfire ... according to the Cubans. In addition to the four people killed, six other people on board the speedboat were wounded in the shootout.

Cuba's government said the injured people on the Florida speedboat were evacuated and received medical attention.

According to the New York Times, a U.S. official says the shootout involved a U.S. civilian boat that was part of a flotilla seeking to get relatives out of Cuba.

Florida Rep. Carlos Gimenez, a Cuban-American and the former mayor of Miami, called the firefight a "massacre" and demanded an "immediate investigation" to determine if the victims were U.S. citizens or legal residents.

The Miami Herald reports Cuba's interior ministry is investigating the incident.

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