Federal prosecutors in New York are preparing additional charges against former Venezuelan President Nicolás Maduro and his wife, Cilia Flores, connected to the alleged torture of Americans detained in Venezuela, CNN reported Wednesday, citing multiple people familiar with the investigation.

The new charges could be announced as early as Thursday, according to the report.

The case centers on more than a dozen US citizens whom the US government has said were wrongfully detained in Venezuelan prisons while Maduro headed what Washington described as a repressive regime.

Investigators have also considered bringing charges against several other individuals accused of involvement in the alleged torture of the detained Americans, a source familiar with the investigation told CNN.

Maduro and Flores were captured during a US military raid on the presidential palace in Caracas in January and subsequently brought to New York.

Both have pleaded not guilty to charges including narcoterrorism conspiracy and are currently being held without bail in New York.