A Venezuelan court has ordered that detained opposition politician Leopoldo Lopez remain in custody pending further hearings, Mr Lopez's lawyer said.
Lawyer Bernardo Pulido tweeted that the court had "confirmed the detention order".
Mr Lopez, of the opposition Popular Will party, was arrested on Tuesday on charges of inciting violence following a wave of anti-government protests.
It is not yet clear when the next hearing will take place.
Mr Lopez's wife Lilian Tintori also posted a message on Twitter calling on her husband's supporters to "not give up". "Change is in each one of us," she wrote.
Supporters of Mr Lopez had gathered at the Palace of Justice in Caracas, where the hearing had been expected to be held.
But after several delays, it was moved to the Ramo Verde prison, where Mr Lopez has been held since he handed himself over to the authorities on Tuesday.
President Nicolas Maduro accused Mr Lopez of fomenting a coup against his government.
"Someone is responsible for every violent act that happens in this country. One of them is in jail," he said in an address on national television.
"The others will get there one by one, in the same way, to the same cell. I have no doubt of that," he warned.
The authorities had issued an arrest warrant for Mr Lopez last week on charges of inciting violence after three people were shot in anti-government protests on 12 February.
After briefly disappearing from the public eye, Mr Lopez posted a video message calling on his supporters to join him in a mass rally on Tuesday, during which he would hand himself in to the security forces.
After giving an impassioned speech standing in front of a statue of Cuban independence hero Jose Marti, Mr Lopez, clutching a white flower, walked up to a line of National Guardsmen and turned himself in.
Tens of thousands of his supporters watched as he was driven away in an armoured vehicle.
Following his detention, a pre-recorded video message by Mr Lopez was posted on video-sharing site YouTube, in which he told his supporters he had been "unjustly detained for dreaming of a better Venezuela".
"If you're watching this video it is because another abuse has been carried out by the government, which is seeking to spread falsehoods, twisting and manipulating events," he said.
"I don't regret any of the things we have done," he insisted.
The government has accused Mr Lopez of fomenting unrest by urging Venezuelans to take part in rallies, some of which have ended in violence.
President Maduro has called the opposition politician a "murderer" and alleged he is being paid the the US Central Intelligence Agency to topple his government.
The authorities point to Mr Lopez's participation in street protests in 2002 which preceded a brief coup against then President Hugo Chavez, Mr Maduro's predecessor in office and mentor, to back up their claims.