Cuba says 4 killed on Florida-registered speedboat were attempting 'infiltration'

Four people on a speedboat were killed and another six injured in a "confrontation" near Cuba's coast after those on board the United States-registered vessel opened fire on Cuban troops on Wednesday, according to the Cuban Ministry of the Interior.

In a statement Wednesday night, the ministry said the 10 people aboard the speedboat were "Cuban residents of the United States," who were armed with weapons and "intended to carry out an infiltration for terrorist purposes."

The U.S. government has not provided specifics about the incident.

The six people who survived have been detained, the ministry said.

The ministry said most of those aboard the boat "have a known history of criminal and violent activity."

The Cuban government said it had also detained another man, "a citizen sent from the United States to facilitate the reception of the armed infiltration," who was arrested.

The incident unfolded Wednesday morning, the ministry said in an earlier statement. As Border Guard troops approached the boat for identification after it was detected in Cuban waters, those on board the speedboat "opened fire," injuring the commander of the Cuban vessel, the ministry said.

The ministry said assault rifles, handguns, Molotov cocktails, bulletproof vests, telescopic sights and camouflage uniforms were seized.

The speedboat was registered in Florida, according to the ministry. It approached Wednesday morning about 1 nautical mile northeast of the El Pino channel, in Cayo Falcones in the Villa Clara province, the ministry said.

"In the face of current challenges, Cuba reaffirms its determination to protect its territorial waters, based on the principle that national defense is a fundamental pillar of the Cuban State in safeguarding its sovereignty and ensuring stability in the region," the Cuban Ministry of the Interior said.

Vice President JD Vance told reporters Wednesday afternoon that Secretary of State Marco Rubio briefed him on the incident and they are monitoring it, "but we don't know a whole lot of details."

"Hopefully it's not as bad as we fear it could be, but I can't say more because I just don't know more," he said during an unrelated press conference.

Diplomats at the U.S. embassy in Havana were still working to get access to the people on the vessel, to determine if they are American citizens or permanent residents, Rubio told reporters.

"The majority of the information we still possess is what Cuban authorities are providing both the public and the U.S. government," he said while speaking from Saint Kitts on Wednesday.

"As we gather more information, then we'll be prepared to respond accordingly," he said.

Rubio noted there were "a number of things" that could have happened, but he wasn't going to speculate.

"Suffice it to say, it is highly unusual to see shootouts in open sea like that," he added. "It's not something that happens every day. It's something frankly that hasn't happened with Cuba in a very long time."

The boat involved in the shooting was registered to a 65-year-old man who was born in Cuba, but is living in Miami, according to multiple law enforcement officials.

FBI agents spoke to the owner of the boat, according to multiple officials.

Preliminary information indicated that the owner reported the boat stolen and is not considered a suspect. The boat was docked at a Florida Keys marina prior to it being stolen.

The FBI Miami field office did not respond to ABC News' request for comment.

Florida officials said they are opening an investigation into the incident.

"I've directed the Office of Statewide Prosecution to work with our federal, state, and law enforcement partners to begin an investigation," Florida Attorney General James Uthmeier said in a statement on X. "The Cuban government cannot be trusted."

Some of Florida's congressional delegation have also demanded an investigation.

"United States authorities must determine whether any of the victims were U.S. citizens or legal residents and establish exactly what occurred," Rep. Carlos Gimenez said in a statement, calling the incident a "massacre."

Sen. Rick Scott also said a "full investigation into this deeply concerning situation" is needed to determine what happened.