Venezuelan state television broadcast on Wednesday a video of captured American Luke Denman, in which he said he was instructed to seize control of Caracas's airport and bring in a plane to fly President Nicolas Maduro to the United States.

Venezuelan authorities on Monday arrested Denman, another US citizen, Airan Berry, and 11 other "terrorists" in what Maduro has called a failed plot coordinated with officials in Washington to enter the country via the Caribbean coast and oust him.

"Donald Trump is the direct chief of this invasion," Maduro said in televised comments, after the video of Denman was broadcast.

Jordan Goudreau, head of Florida-based security company SilverCorp USA and a US military veteran, has claimed responsibility for the incursion. Goudreau said he was working with two US citizens in an operation designed to capture, not kill, Maduro and "liberate" Venezuela.

The Associated Press news agency reported on Wednesday that Goudreau is currently under federal investigation for arms trafficking. The investigation is in its initial stages and it’s unclear if it will result in charges, a law enforcement official told the AP, and stems from a frenzy of contradictory comments Goudreau has made since Sunday's raid.

Members of the US Congress are also asking the State Department about its knowledge of Goudreau’s plans and raised concerns that he possibly violated arms trafficking rules.

An AP investigation published prior to the failed raid places Goudreau at the center of a plot hatched with a rebellious former Venezuelan Army General, Cliver Alcalá, to secretly train dozens of Venezuelan military deserters in secret camps in Colombia to carry out a swift operation against Maduro.

Goudreau’s possible involvement in weapons smuggling stems from the March 23 seizure by police in Colombia of a stockpile of weapons being transported in a truck. The stockpile, worth around $150,000, included spotting scopes, night vision goggles, two-way radios and 26 American-made assault rifles with the serial numbers filed off.

Maduro said on Wednesday that he would seek Goudreau's extradition from the US.

US President Donald Trump has denied involvement in Sunday's ill-fated mission. Secretary of State Mike Pompeo said on Wednesday that the US government would use "every tool" to secure the Americans' return if they were being held in Venezuela.

Denman, 34, in the video statement from an undisclosed location, answered questions from a person off-camera speaking in English. Denman said his mission was to secure the airport and establish a security perimeter, though it was unclear how he planned to get Maduro on a plane.

In March, the US Department of Justice charged Maduro and a dozen other current and former Venezuelan officials with "narco-terrorism" and the Trump administration offered a reward of $15m for information leading to his arrest.

"I was helping Venezuelans take back control of their country," Denman said in the video.

The alleged assassination plot comes at a time of high tensions between the US and Venezuela.

The US is among nearly 60 countries that back opposition politician Juan Guaido as Venezuela's legitimate leader. It has also imposed tough economic sanctions against Caracas in an effort to force Maduro, whom it accuses of having rigged elections in 2018, to step down.

The AP news agency reported that six people were killed on May 3 as they tried to enter Venezuela, citing Venezuelan government reports.