The wives of Venezuelan opposition leaders Leopoldo López and Antonio Ledezma say their husbands have been re-arrested.
The two men were under house arrest after being found guilty of inciting violence during anti-government protests in 2014.
Their wives said they did not know where the two had been taken.
The move comes just two days after a controversial vote for a constitutional assembly saw violence on the streets.
Days before the vote, Mr López had released a video on YouTube calling on Venezuelans to take to the streets in protest.
Mr López was transferred from a military prison to house arrest on 8 July after spending more than three years in jail.