Venezuelan authorities arrested three Americans, two Spaniards and a Czech national on Saturday after officials accused them of coming to South America to assassinate President Nicolas Maduro.

The arrests were announced on state television by Diosdado Campejothe Minister of the Interior, Justice and Peace of Venezuela. Cabejo said the foreign nationals were part of a CIA-led plot to overthrow the Venezuelan government and assassinate several members of its leadership. In fact, Campejo showed images of rifles that he said were seized from some of the conspirators in the alleged plot.

Among the Americans arrested is one of its executives Navywhom Campejo identified as Wilbert Joseph Castaneda Gomez. Cabejo said Gomez has served in Afghanistan, Iraq and Colombia. However, Spain’s embassy in Venezuela declined to comment on the arrests of its citizens.

The US State Department confirmed late Saturday the detention of a US serviceman and was aware of “unconfirmed reports that two additional US citizens are being held in Venezuela.”

“Any allegation of US involvement in a plot to overthrow Maduro is categorically false. The United States continues to support a democratic solution to the political crisis in Venezuela,” the statement said.

The announcement of the arrests comes just two days after the US Treasury Department sanctioned 16 Maduro allies accused by the US government of obstructing voting in Venezuela’s disputed July 28 presidential election and human rights abuses.

Earlier this week, the Spanish Parliament recognized the opposition candidate Edmundo Gonzalez Urutia as the winner of the election, angering Maduro’s allies who have called on the Venezuelan government to cut trade and diplomatic ties with Spain.

Tensions between the Venezuelan government and the US have also risen since the election, the result of which sparked protests in Venezuela in which hundreds of opposition protesters were arrested.

The Electoral Council of Venezuelawhich is closely aligned with the Maduro government, said Maduro won the election with 52 percent of the vote, but did not elaborate on the results.

Despite international condemnation for the lack of transparency of the elections, the Supreme Court of Venezuelawhich has long supported Maduro, confirmed his victory in August. Venezuela’s Attorney General then filed conspiracy charges against Gonzalez, who fled to Spain last week after it became clear he would be arrested.

Maduro has rejected requests from several countries, including the leftist governments of Colombia and Brazil, to provide electoral data proving he won the election. Maduro, who has been in power since 2013, has long claimed the US is trying to topple him through sanctions and covert operations.