Demonstrators have clashed with riot police in Caracas after a march against the arrest of two opposition mayors accused of failing to stop violence in protests that have rocked Venezuela.
Some 3,000 people rallied on Thursday against the socialist government of the president, Nicolas Maduro, before a group of protesters threw rocks at police who responded with tear gas and water cannon.
The latest demonstration came a day after domestic intelligence agents arrested Daniel Ceballos, the mayor of San Cristobal, the western city where the first protests erupted on February 4 before spreading to other cities.
Ceballos was accused of encouraging "civilian rebellion" in his city.
Separately, the mayor of the northern town of San Diego, Enzo Scarano, was stripped of his post by the Supreme Court and sentenced to 10 months in prison on charges that he failed in his duty to stop public disorder.
Maduro warned that their colleague in Chacao, a wealthy suburb of eastern Caracas, could be next if barricades were built in his streets.
The mayors of San Diego and San Cristobal were locked up at the Ramo Verde military prison outside the capital, the same site where the authorities are holding opposition leader Leopoldo Lopez, who has promoted protests aimed at ousting Maduro.
The ruling party in the unicameral national assembly voted to request an investigation of another opposition figure, legislator Maria Corina Machado, accusing her of "instigating delinquency, treason, terrorism and homicide".
Machado, during a visit to Washington ahead of an address Friday at the Organisation of American States, said she would remain "firm about our right to protest".