Two Americans, including one member of the 'CITGO6,' released from prison in Venezuela

This undated file photo posted on Twitter on June 18, 2020, by Venezuela's Foreign Minister Jorge Arreaza, shows former CITGO oil executives Jose Angel Pereira, from left to right, Gustavo Cardenas, Jorge Toledo, Jose Luis Zambrano, Tomeu Vadell and Alirio Jose Zambrano, standing outside the Bolivarian National Intelligence Service, in Caracas, Venezuela.

(CNN)At least one American member of the so-called CITGO 6 has been released from prison in Venezuela, a lawyer assisting several of the CITGO 6 and a spokesman from a Venezuelan nongovernmental organization that's providing legal assistance to prisoners in the country both told CNN.

Gustavo Cárdenas, a US citizen detained in Caracas since 2017 who's one of six former oil executives of the US refinery CITGO, was released from prison on Tuesday evening, the lawyer and the NGO said.

Jorge Alberto Fernandez, a Cuban-US dual citizen detained in Venezuela since February 2021, was also released from prison on Tuesday, his lawyer Maria Alejandra Poleo told CNN.

Fernandez, who is not one of the CITGO 6, had been detained in the western city of San Cristobal shortly after entering Venezuela from neighboring Colombia. He was accused of terrorism for carrying a small domestic drone, Poleo told CNN. Flying a drone without a license is illegal in Venezuela.

The releases follow a high-profile visit by US officials to Caracas on Saturday -- the first since diplomatic relations between the two countries broke down in 2019.

President Joe Biden praised the release of the two men in a statement Tuesday night, saying they were "wrongfully detained" and will now "be able to hug their families once more."

The President said that unjustly holding Americans captive was always unacceptable.

"And even as we celebrate the return of Cardenas and Fernandez, we also remember the names and the stories of every American who is being unjustly held against their will -- in Venezuela, in Russia, in Afghanistan, Syria, China, Iran, and elsewhere around the world. My Administration will keep fighting to bring them all home," Biden said.

Lawyers and relatives of the CITGO 6 have often accused Venezuelan embattled leader Nicolas Maduro of using the group as "pawns" to exert pressure on the US government. In recent months, the men were taken to prison from house arrest in apparent retaliation for the US extradition of Alex Saab, a Colombian financier close to Maduro.

The group consists of Cárdenas, José Ángel Pereira, Jorge Toledo, José Luis Zambrano, Tomeu Vadell and Alirio José Zambrano. The former executives of CITGO Petroleum Corp. were arrested in 2017 in Caracas on embezzlement charges, which they deny.

US National Security Council Senior Director for the Western Hemisphere Juan Gonzalez and US Ambassador James Story met with Maduro and his wife in Caracas to discuss the health of US citizens detained in Venezuela and the state of US sanctions on the Venezuelan oil market, both the US government and the Venezuelan government said on Monday.

The current whereabouts of Cárdenas and Fernandez are unclear, although former prisoners in similar circumstances in the past were allowed to fly to the United States hours after their release.

This story has been updated with additional reporting Tuesday.