U.S. prosecutors are investigating several high-ranking Venezuelan officials, including the president of the country’s congress, on suspicion that they have turned the country into a global hub for cocaine trafficking and money laundering, according to more than a dozen people familiar with the probes.

An elite unit of the Drug Enforcement Administration in Washington and federal prosecutors in New York and Miami are building cases using evidence provided by former cocaine traffickers, informants who were once close to top Venezuelan officials and defectors from the Venezuelan military, these people say.

A leading target, according to a Justice Department official and other American authorities, is National Assembly President Diosdado Cabello, considered the country’s second most-powerful man.

Leamsy Salazar, who had previously worked for late President Hugo Chávez’s security detail, is currently in Washington, where he is expected to provide witness testimony implicating Mr. Cabello in organizing cocaine-smuggling operations controlled by Venezuela’s military, two people familiar with the matter said.

Salazar certainly ought to be in the know. Prior to turning state’s witness, he spent over a decade as the head of Hugo Chávez’s personal security detail and sometime personal assistant; a YouTube video currently making the rounds on Venezuelan social media even shows El Comandante singing Salazar’s praises on TV. Following the death of Chávez in early 2013, Salazar was reassigned to Cabello, whom he is prepared to depict in court, according to ABC, as the capo di tutti capi of the “Soles” narcotics cartel.

An post shared on Twitter by Ramón Pérez-Maura, an ABC journalist covering the case, stated that Salazar’s testimony had also linked Cuba with the country’s narcotrafficking trade, “offering protection to certain routes along which drugs were brought to Venezuela from the United States.”

Two nephews of Venezuela's first lady are facing arraignment in New York after being arrested in Haiti on charges of conspiring to smuggle 800 kilograms of cocaine into the U.S., according to people familiar with the case.

Both men were carrying diplomatic passports even though they don't have diplomatic immunity, he said.

The case also comes just three weeks before key legislative elections that opinion polls have suggested could hand the ruling party its worst defeat in 16 years as Venezuela's struggles with triple-digit inflation and widespread shortages of basic goods.

"The timing is hardly ideal," Michael Shifter, president of the Washington-based Inter-American Dialogue think tank, said in an email after the arrests were revealed Wednesday. "The arrests could give Maduro the excuse he was hoping for to declare a state of emergency and postpone the elections. He will blame the arrests on U.S. imperialism and see them as an attempt to undermine his government."

"The homeland will continue its course. Neither attacks nor imperialist ambushes can harm the Liberator's people," Maduro wrote, alluding to South American liberator Simon Bolivar, who is an icon of Maduro's movement.

Flores, who Maduro calls the "First Combatant," is one of the most influential members of Venezuela's revolutionary government and a constant presence alongside her husband whenever he appears in public.

American prosecutors have been steadily stepping up pressure on high-ranking members of Venezuela's military, police and government officials for their alleged role in making the country an important transit zone for narcotics heading to the U.S. and Europe. The U.S. government says more than 200 tons a year of cocaine flows through Venezuela, about a third of Colombia's estimated production.

But while several Venezuelan officials, including a former defense minister and head of military intelligence, have been indicted or sanctioned in the U.S., and many more are under investigation, no drug probes had previously touched Maduro's inner circle.