The United States (US)  has announced criminal charges against former Cuban President Raúl Castro in the latest escalation of tensions between the two countries, according to US media.

A report from CNN Wednesday afternoon indicated the case being brought against the now 94-year-old brother of revolutionist Fidel Castro was unsealed Wednesday.

Raul is reportedly charged with conspiracy to kill US nationals, destruction of an aircraft, and murder, alongside several other defendants listed in the indictment.

The charges reportedly stem from a 1996 incident where two civilian aeroplanes were shot down, killing four men, including three American citizens. At the time, Castro was Cuba’s defence minister and is alleged to have ordered the attack.

The aircrafts reportedly belonged to the Cuban-American exile organization Brothers to the Rescue.

The left-leaning US news organisation described the case as “an extraordinary example of the administration’s use of its Justice Department to target the leader of a country it opposes, guaranteeing a rise in tensions between the longtime foes”.

The potential indictment was reported days earlier and follows a major military operation carried out by the United States in Venezuela, where then-President Nicholás Maduro was kidnapped and brought to the United States.

Maduro is now in a New York prison on drug-trafficking charges.

President Donald Trump has also threatened military action against Cuba before too, saying in March that the Caribbean country “is gonna fall pretty soon” and that “I think I could do anything I want with it.”

Secretary of State Marco Rubio, the son of Cuban immigrants, has publicly opposed the current regime in Cuba.