WASHINGTON — The Trump administration announced sweeping indictments Thursday of Venezuelan President Nicolas Maduro and some of his associates on federal drug-trafficking and related charges, in a major escalation of the U.S.-led campaign to topple Maduro and his socialist government.

The charges, described by Attorney General William Barr at a news conference in Washington, allege that Maduro and members of his inner circle conspired with rebels from neighboring Colombia to create a vast and lucrative criminal enterprise in Venezuela "flooding" the United States with cocaine and generating billions in illicit dollars. Maduro and his allies pocketed profits, and the rebels received weapons, prosecutors allege — all while Venezuela descended into poverty and social collapse.

"The Maduro regime is awash in corruption and criminality," Barr said. It has "betrayed the Venezuelan people and corrupted Venezuelan institutions. While the Venezuelan people suffer, this cabal lines their pockets with drug money and proceeds of the corruption. This has to come to an end."

The indictment naming Maduro means he would be subject to arrest if he leaves Venezuela. The U.S. State Department immediately put out a $15-million reward for information leading to his capture.

Barr would not discuss whether the administration might attempt to extradite Maduro — or extract him in a military operation. He said he expected Maduro and others charged in the multiple indictments and one complaint to be tried in U.S. courtrooms.

In Caracas, Maduro responded even before Barr finished speaking. It's a conspiracy from the United States and Colombia, he railed, and "they have given the order to fill Venezuela with violence!" He said he would defend "peace and homeland" against "whatever circumstances present themselves."

It is unusual for the U.S. government to indict a sitting president. The last time such an action was taken was the 1988 indictment of Gen. Manuel Noriega, the powerful and wildly corrupt leader of Panama. A year later, then-President George H.W. Bush invaded Panama and captured Noriega, and he was convicted on trafficking and money-laundering charges.

While U.S. officials often draw parallels between the ways Noriega and Maduro transformed their countries into criminal havens, an invasion-and-capture scenario for Venezuela is seen as highly unlikely. Panama was at the time a small country with a U.S. military presence tied to the Panama Canal. Venezuela by contrast is vast, and Maduro enjoys formidable military support from Russia and Cuba.

The Trump administration — propelled by hawks like former National Security Adviser John Bolton — has sought for more than a year to oust Maduro while the country plunges into economic decay. But the effort has floundered. The administration does not recognize Maduro and has thrown its support behind Juan Guaido, head of the opposition.

The timing of the action raised questions within the foreign policy community and those who follow Venezuelan issues. It comes as Venezuela — its health system already teetering — is being overwhelmed by the coronavirus pandemic, which may make Maduro more open to political negotiations.

"For the first time in a long time, Maduro needs the opposition" for access to international aid to fight the pandemic, said David Smilde, a Tulane University professor who is a fellow at the Washington Office on Latin America. Indicting Maduro now will make him feel cornered and less likely to cooperate.

"This ups the pressure, but it ups Maduro's exit price even more," he said. "It's hard to imagine he would not hunker down. Why negotiate now if you have an indictment hanging over your head?"

Electoral politics have long been at the core of Trump's focus on Venezuela, former officials say, and, with the voting barely seven months away in the U.S., he may be eager to topple the regime in Caracas to energize conservative voters in southern Florida.

Barr said the investigation had been underway for quite some time. Prosecutors were going to announce the charges a week or so ago, he said, but held off to figure out how to manage a press conference and unveiling of charges amid social distancing requirements aimed at slowing the spread of spread of coronavirus.

Barr said announcing the indictments during a global pandemic could help further motivate Venezuelans to jettison Maduro from power.

"It's good timing, actually," Barr said. "The people in Venezuela are suffering, and they need an effective government that responds to the people."

"The regime feeds at the trough, blocking supplies and help to the Venezuelan people from coming in," Barr added. "This is the best way to support the Venezuelan people: To rid this country of this corrupt cabal."

Charges were also filed against 14 other Venezuelan government officials, including the head of the supreme court and military commanders, who were allegedly part of a drug-trafficking effort which started more than a decade ago under the government of the late Hugo Chavez.

Vladimir Padrino Lopez, 56, the defense minister, was indicted on charges of allowing drug dealers who paid him bribes in a five-year span starting in 2014 to safely transit his country's airspace while ordering others to be shot down or forced to land.

Jose Moreno Perez, 54, the chief justice of Venezuela's supreme court, was charged in a criminal complaint with conspiring to commit money laundering by accepting tens of millions of dollars in bribes to "illegally fix dozens of civil and criminal cases," the Justice Department said. The complaint alleged that Perez authorized the seizure and sale of a General Motors plant worth about $100 million in exchange for a percentage of the proceeds. He also released Venezuelans from custody who paid him bribes, including one accused of participating in a multi-billion dollar fraud scheme, the complaint alleges.

Indicted by a federal grand jury in New York on participating in a narco-terorrism conspiracy, conspiring to import cocaine to the U.S. and related charges were: Maduro, 57; Diosdado Cabello Rondon, 56, the head of the National Constituent Assembly; Hugo Armando Carvajal Barrios, former director of military intelligence; and Cliver Antonio Alcala Cordones, 58, a former general.

The indictment alleges that Maduro and the others for years had been members of the Cartel de los Soles ("Cartel of the Suns)", named for the sun insignia affixed to the uniforms of high-ranking military commanders.

They were accused of helping Colombian rebels — the Fuerzas Armadas Revolucionarias de Colombia, or FARC — import cocaine from Colombia into Venezuela and fly it to Central America to be distributed to the United States. Barr characterized the shipping effort as an "air bridge."