Cuba criticised the US government for allowing anti-Cuban groups to operate with impunity on Thursday, as Cuban exiles wounded in an apparent attack aboard a Florida-registered speedboat convalesced at a provincial Cuban hospital.

The government in Havana said heavily armed Cuban nationals tried to infiltrate the country by speedboat on Wednesday, leading to gunfire at sea in which Cuban forces killed four Cuban nationals and wounded six others, who were in Cuban custody.

According to a US official in Washington, at least two of those aboard the speedboat were US citizens, one of the dead and one of the injured, who was receiving medical care in Cuba.

Others may have been legal US residents, the official said.

While Cuba laid blame at the US for allowing anti-Castro groups to operate freely, it also said it had been in communication with US officials since the outset of Wednesday’s incident, saying the Americans in turn showed a willingness to cooperate on clarifying what happened.

The boat’s owner alleged that the vessel was stolen by an employee, the US official said.

The deadly confrontation took place at a tense moment in the frequently antagonistic US-Cuban relationship.

US President Donald Trump has further tightened economic sanctions on Cuba since the US captured Venezuelan President Nicolas Maduro, a key Cuban ally, on January 3.

Fernando de Cossio, a senior foreign ministry official, told reporters in Havana on Thursday that Cuba has in the past alerted the United States to an “increase in violent and terrorist plans and actions against Cuba” by groups and individuals in US territory, but that the US has failed to act.

“Anti-Cuban groups operating in the United States resort to terrorism as an expression of their hatred of Cuba and the impunity they believe they enjoy,” de Cossio said in a prepared statement.

He did not take questions.

He said two of the assailants were previously wanted for plotting attacks and were on a list of suspects shared with the United States.

Cuban exiles who are largely concentrated in Miami have long dreamed of overthrowing Cuba’s Communist government or seeing it fall, and Cuban exile paramilitaries have attempted or carried out acts of sabotage in the past.

The suspects came from the US dressed in camouflage and armed with assault rifles, handguns, homemade explosives, ballistic vests and telescopic sights, Cuba said.

U.S. Secretary of State Marco Rubio said on Wednesday his government would independently investigate the incident and that the US Embassy in Havana was seeking access to the survivors to determine whether any were US citizens or permanent residents.

He said it was not a US operation and that no US government personnel were involved.

HOSPITAL UNDER HEAVY GUARD

Cuba said the six survivors were receiving medical attention.

At least some of them appeared to be in custody at the Arnaldo Milian Castro Provincial Clinical Surgical Hospital in Santa Clara, about 250 km (150 miles) east of Havana.

Santa Clara is the capital of the province where the incident was reported to have taken place, about one nautical mile off a northern cay.

The civilian hospital was under heavy guard.

Security personnel who stopped Reuters journalists near the entrance confirmed the suspects were held there but provided no further details.

Uniformed Interior Ministry troops came and went from the hospital.

Cuban President Miguel Diaz-Canel, whose government has been dealing with an acute oil shortage since the US halted flows from Venezuela and threatened to impose tariffs on any country delivering oil to Cuba, issued a defiant statement on X earlier on Thursday.

“Cuba will defend itself with determination and firmness against any terrorist and mercenary aggression that seeks to affect its sovereignty and national stability,” Diaz-Canel said.

SUSPECTS IDENTIFIED

Cuba said two of the detainees - Amijail Sanchez Gonzalez and Leordan Cruz Gomez - were previously wanted and appeared on a 2025 list of suspects that Cuba deemed as terrorists.

Sanchez was accused of involvement in a plot against a municipal court and a Communist Party organisation in Havana, and Cruz was suspected of arms trafficking in a purported attack on a military unit in Matanzas.

Both are aged 47 and Cuba-born US residents, according to a report filed with Cuba’s official gazette.

The other wounded survivors were identified as Cristian Ernesto Acosta Guevara, Conrado Galindo Serrior, Jose Manuel Rodriguez Castello and Roberto Alvarez Avila.

Galindo was briefly detained in Cuba on at least one occasion, according to the Cuban Commission for Human Rights and National Reconciliation, an inactive group that previously reported allegations of Cuban repression.

Cuba identified the four dead as Pavel Alling Peña, Michael Ortega Casanova, Ledian Padron Guevara and Hector Duani Cruz Correa.

Cuba also said it previously had incorrectly identified Rolando Roberto Ascorra Consuegra as a suspect, saying now he was uninvolved.