The arrests come amid heightened tensions between Caracas and Western nations over disputed Venezuelan election results.
Venezuela has detained three U.S. citizens, two Spaniards and a Czech national over an alleged plot to destabilize the South American nation, a senior government official said.
Venezuelan Interior Minister Diosdado Cabello said Saturday that the six were detained on suspicion of planning an attack against President Nicolas Maduro and his government.
The arrests come as tensions have soared in recent weeks between Venezuela and the United States, Spain and other Western nations over disputed Venezuelan elections held in late July.
Maduro, who has been in power since 2013, was declared the winner of the election but the country's opposition said the contest was riddled with fraud and that its candidate had defeated the long-serving president.
The election results sparked mass opposition protests, leaving more than two dozen people dead and nearly 200 injured.
During a press conference on Saturday, Cabello accused the two detained Spanish citizens of having alleged links with the Spanish secret service and of planning the murder of a mayor.
The couple was arrested while taking photos in the town of Puerto Ayacucho, the minister said.
Spanish media reported that the Spanish government denied this claim.
Cabello also accused three U.S. citizens and a Czech citizen of participating in “terrorist” acts, including alleged plans to assassinate Maduro and other officials.
“These groups are seeking to seize the country's wealth and we as a government will respond firmly to any attempt at destabilization,” Cabello said.
He added that around 400 rifles of US origin have been seized.
A U.S. State Department spokesman told Reuters news agency that “one U.S. military member” had been detained in Venezuela and that he was aware of unconfirmed reports that two other U.S. citizens were detained there.
But the State Department said the United States was not involved in an attempt to overthrow Maduro.
“Any claim that the United States is involved in a plot to overthrow Maduro is categorically false,” the spokesperson said. “The United States continues to support a democratic solution to the political crisis in Venezuela.”
Venezuela recalled its ambassador to Spain this week and summoned the Spanish ambassador to appear at the Foreign Ministry after a Spanish minister accused Maduro of running a “dictatorship.”
Venezuela was also outraged by Spanish Prime Minister Pedro Sanchez's decision to meet with Venezuelan opposition candidate Edmundo Gonzalez, who fled to Spain last week after being threatened with arrest by Maduro's government.
Caracas has also faced renewed tensions with Washington, which recognized Gonzalez as the winner of the July 28 elections.
The United States also imposed new sanctions on Venezuela earlier this week.
