Nobel laureate Maria Corina Machado suffered a fractured vertebra while being smuggled out of Venezuela on a small fishing boat, it emerged on Monday.
The opposition leader, 58, donned disguises and braved choppy waters in a bid to collect her Nobel Peace Prize in Norway last week in defiance of a decade-long travel ban.
The daring voyage was fraught with bad weather, and her spokesperson confirmed local reports that she fractured part of her spine during the journey.
Norwegian daily Aftenposten had reported that doctors at an Oslo hospital had identified several injuries, including the fractured vertebra, when she arrived.
Ms Machado had said previously that she feared for her life during the three-day expedition out of the country and on to Norway via the United States.
She had hoped to arrive in Oslo by Wednesday to collect her Nobel Peace Prize, but was delayed until Thursday and missed her ceremony.
She and two companions had snuck through 10 military checkpoints last Monday to reach the Venezuelan coast and sail on to the island of Curaçao before being flown to Norway via Maine in the United States.
Before sailing from Venezuela, they had to tell the US military of their movements to avoid being mistaken for so-called narcoterrorists in the region and “blown up”, according to a source close to the operation.
When Ms Machado finally arrived in Norway, she waved to supporters from the balcony of her hotel despite her injuries.
She has said she plans to return to Venezuela, and that her aim is to achieve a peaceful transition of government from President Nicolas Maduro.
Speaking on Face the Nation on Sunday, Ms Machado also voiced support for Trump’s controversial jostling against Maduro in recent weeks.
The US has amassed a fleet of ships in the Caribbean in what Maduro believes is a bid to force him out of power.
Ms Machado said on Sunday that she “absolutely supports President Trump's strategy” and is sure that the people of Venezuela are “very grateful to him”.
The US has built up its biggest naval presence in the region in three decades since August, based on accusations that the country ships narcotics to the United States. The Venezuelan government has denied the charges.
Trump and pro-democracy activist Ms Machado have found an unlikely alignment since she beat him to the Prize in October. The White House at the time accused the Nobel Committee of choosing “politics over peace”.
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