CARACAS, May 7 (REUTERS) - Members of Venezuela's opposition in October negotiated a $213 million deal with a small Florida security company to invade the country and overthrow President Nicolas Maduro, according to a document published by the Washington Post on Thursday.

Venezuelan authorities this week arrested more than a dozen people, including Americans who work for the company, Silvercorp USA, as part of a bungled incursion that has served as a public relations victory for Maduro's struggling government.

The two captured Americans appeared on state television in Venezuela on Wednesday and Thursday, saying they had been tasked by Silvercorp with taking control of the airport in Caracas in order to fly out Maduro. Both will be tried in Venezuela's civilian courts, Maduro said.

The document deals a blow to the credibility of opposition leader Juan Guaido, who has vehemently denied any links to Silvercorp or involvement in the attempt to remove Maduro by force.

Guaido, the president of the opposition-controlled National Assembly, argues that Maduro is usurping power after rigging a 2018 election. Guaido is recognized by dozens of countries as Venezuela's rightful leader.

The plan described in the 42-page document offers minute tactical details ranging from which land mines to deploy and what riot gear to use, but offers no explanation of how a small group of commandos could overpower hundreds of thousands of security forces who remain loyal to the ruling Socialist Party.

On Thursday, state television aired a video with captured American Airan Berry, who said the objectives of the mission were to control specific targets such as intelligence service Sebin and military intelligence group DGCIM and to "get" Maduro.

Asked about the reported document and Berry's television appearance, a U.S. State Department spokesman said: "There is a major disinformation campaign underway by the Maduro regime, making it difficult to separate facts from propaganda."

Maduro in an interview on Thursday said informal channels of communication between Caracas and Washington had gone dead since the failed incursion.

"There have always been links, since May 3 they've been cut off," Maduro said in the interview on the Telesur television network. "They're mute. Total silence."

The document published by the Washington Post said, "Service Provider Group will advise and assist Partner Group in Planning and executing and operation to capture/detain/remove Nicolas Maduro (heretoafter "Primary Objective"), remove the current Regime, and install the recognized Venezuelan President Juan Guaido."

Reuters was unable to immediately confirm the authenticity of the document https://context-cdn.washingtonpost.com/notes/prod/default/documents/6241a047-6222-4269-8c50-2c9e3c7c9cf5/note/d836cf76-031f-4978-a4da-18a081752b94, which the Washington Post said had been provided by Venezuelan opposition officials.

Guaido's press team did not respond to a request for comment.

Guaido adviser Juan Rendon, whose signature allegedly appears on the document, said in a telephone interview that he negotiated the agreement, but that Silvercorp's chief executive, Jordan Goudreau, went ahead with it even though Rendon had cut ties with him in November.

"He went out on his own," Rendon said.

Reuters was unable to obtain comment from Goudreau, who has publicly described leading the operation.

Two main opposition parties, First Justice and Popular Will - which Guaido is affiliated with - on Thursday said in a statement that "the democratic forces do not promote or finance guerrillas, outbreaks of violence or paramilitary groups," reiterating calls for a transition government.

The logos of six other parties, including Democratic Action and A New Era, which have significant representation in the National Assembly, appear on the document.