In Venezuela, You’re a Critic One Day, and Arrested the Next

Of all the government critics, few thought that Rocío San Miguel would be the one to disappear.

Ms. San Miguel, 57, has long been one of Venezuela’s best known security experts, a woman who dared investigate her country’s authoritarian government even as others fled. She is also a moderate, has international recognition and appeared to have strong contacts in the secretive world of the Venezuelan military, qualities that her peers thought might protect her.

But late last week, Ms. San Miguel arrived at the airport outside Caracas with her daughter, bound for what a relative called a short trip to Miami, when she was picked up by counterintelligence agents. Soon after, her family began to disappear, too. The daughter, two brothers and two former romantic partners. Gone.

For four days, the only public information about Ms. San Miguel came from Venezuela’s top prosecutor, who claimed on social media, without providing evidence, that Ms. San Miguel had been linked to a plot to kill the country’s president, Nicolás Maduro.

Finally, on Tuesday evening, her lawyers said she had surfaced — and was being held in a notoriously brutal detention center. Her family was also in state custody.

The arrest of Ms. San Miguel, the head of a modest but influential nonprofit organization that monitors the armed forces, has triggered a small earthquake in Venezuela’s human rights circles, where just a few months ago many watched with guarded anticipation as Mr. Maduro signed a deal with the country’s opposition, promising to work toward a free and fair presidential election later this year.

Political change, if still a far-off possibility, seemed worth dreaming about.

Now, the small group of activists, aid workers, critics, analysts, journalists and others who have been able to hang on inside the country — despite years of repression and economic crisis — are watching the space in which they operate narrow even further.