He is due in court today, having surrendered to Venezuelan authorities.
But opposition leader Leopoldo Lopez is encouraging his supporters to continue protesting, speaking to them via a pre-recorded video message on Twitter.
Accused of fomenting unrest that has killed at least four people, the 42-year-old Harvard-educated economist handed himself in to soldiers on Tuesday after making a defiant speech at a rally in Caracas.
Later, his Popular Will party released the video of Lopez, sitting alongside his wife.
“If you are seeing this video it is because the Venezuelan state issued an arrest warrant against me,” he said.
“I might already be in the custody of the state’s security forces, detained unjustly for dreaming of a better Venezuela.”
In the deeply-divided nation, supporters of President Hugo Chavez’s Socialist successor Nicolas Maduro have also taken to the streets. They are defending him from opposition anger at issues like inflation, corruption and violent crime.
Student-led protests across the nation of 29 million people have become the biggest challenge to Maduro since his election last year.