Adrián Simancas, 23, was kayaking off Chilean Patagonia when he found himself inside a whale.

The US says the Venezuelan aircraft was involved in violations of US export control and sanctions laws.

The move follows talks between Maduro and a Trump envoy that led to the release of six US detainees.

Attacks between guerrilla groups have also seen thousands displaced from the country's Catatumbo region.

The increased reward was announced on the day Maduro was sworn in for a third six-year term as president.

Nicolás Maduro took the oath before parliament, vowing his third six-year term in office would be a "period of peace".

The opposition says María Corina Machado was then freed on the eve of President Nicolás Maduro's inauguration.

Hundreds were arrested in protests after Nicolás Maduro claimed victory in last year's contested presidential election.