aims". Border guards shot dead four people and injured the other six on the boat, the Cuban interior ministry said, alleging that those on the Florida-registered vessel had fired first. US Secretary of State Marco Rubio said Washington was investigating the "highly unusual" incident. The deadly shooting comes at a time of increased tension between the two countries, less than two months after US forces seized Cuba's close ally, Venezuelan leader Nicolás Maduro, and stopped his successor from supplying it with oil.

Cuba's interior ministry said in an online statement that the speedboat had entered Cuban territorial waters and was "one nautical mile off Cayo Falcones", on the country's northern coast, when it was intercepted. It added that the commander of the Cuban boat was injured in the firefight that ensued. Cuban President Miguel Díaz-Canel said Cuba would "defend itself with determination and firmness against any terrorist and mercenary aggression against its sovereignty and national stability". Cuban officials have so far named one of the men killed in the clash, as well as the six survivors, who they said were evacuated and given medical assistance.

The Cuban authorities said they had established that all 10 of those on board the speedboat were Cuban nationals residing in the US. They also identified an 11th person they said had been arrested and had confessed to being part of the alleged plot. The Cuban authorities added that most of them had "prior records involving criminal and violent activity". Handguns, assault rifles and improvised explosive devices were recovered from the speedboat, along with other tactical gear, according to the statement. BBC Verify checked the speedboat's registration details provided by the Cuban embassy in US (FL7726SH, Florida registered) but they yielded no ownership details or tracking history on any of the platforms the BBC relies on. Cuba's interior ministry has in the past denounced other incursions into its territorial waters by privately owned US boats it said were engaged in smuggling Cubans from the Caribbean island to the US. (BBC)