Venezuelan opposition legislator José Manuel Olivares has fled the country, accusing the government of threatening him and several family members.
In an open letter, Mr Olivares said that in recent weeks secret police agents approached him, his wife and his brother saying they would be persecuted unless he stepped away from politics.
"My family's wellbeing comes first," said Mr Olivares.
Several senior opposition leaders have left Venezuela over the past year.
They say intimidation and harassment by President Nicolás Maduro has made them fear for their lives.
Mr Maduro was re-elected in May to a new six-year term.
The opposition was weakened by the arrests or self-imposed exile of many of its leaders. Most anti-Maduro parties boycotted the vote.
The president blames Venezuela's elite and what he terms imperialist forces led by the United States for the country's economic crisis.
This week, the government announced it was cutting five zeroes from the currency, the bolívar.
Critics say this will have little effect in curbing the world's highest inflation rate, estimated at 46,000% a year.
'Not prepared for this'
Mr Olivares, who is also a doctor, said his family was taken by surprise by the recent levels of intimidation from the secret police, Sebin.
"We were not prepared for this neither politically, financially or emotionally," he wrote from Colombia.
"They were now even harassing my wife, who gave birth only a few months ago."
He vowed to continue his political struggle against the Maduro administration from abroad, alongside other dissidents.
"I will highlight the problems faced by patients in the health system, including the chronic shortage of medicines.
"And I will continue to campaign for the opening of a humanitarian channel, to bring food and medicine to the Venezuelan people," Mr Olivares wrote in his letter, which was published on Twitter.