Washington — Former Cuban leader Raúl Castro and five others have been indicted by a U.S. grand jury in Florida, according to court filings made public Wednesday.

The federal criminal charges against the 94-year-old Castro — brother of the late Fidel Castro and widely seen as one of Cuba's most powerful figures — mark an escalation in the Trump administration's pressure campaign against the Cuban government. Castro served as president of Cuba from 2008 to 2018 and as the top official of the country's Communist Party from 2011 to 2021.

CBS News was first to report that the U.S. was preparing to indict Castro in connection with the Cuban military's fatal downing of two civilian planes 30 years ago, killing four people. 

Castro was charged in South Florida with conspiracy to kill U.S. nationals, four counts of murder and two counts of destruction of aircraft, the court docket shows. The exact contents of the indictment aren't clear: A judge on Wednesday granted a motion to unseal a superseding indictment against Castro, but the indictment itself has not yet been made public.

The other defendants include a fighter pilot who was initially charged in connection with the 1996 shootdown more than two decades ago.

It's not clear whether Castro will ever stand trial since Cuba does not extradite people to the United States. Former Venezuelan leader Nicolás Maduro was indicted on drug charges in 2020. Earlier this year, he was captured by U.S. forces and flown to New York for trial, a daring operation that led to the installation of interim President Delcy Rodriguez, who is now working closely with the U.S.

This is a breaking news story and will be updated.