Dozens of people have been injured and a 27-year-old man was killed during another day of violent clashes in Venezuela's capital during demonstrations demanding elections.
National guard officers launched tear gas and a group of armed pro-government militiamen harassed protesters as they tried to march to the Supreme Court.
One masked militia member fired several shots into the air. The militia dispersed after officers intervened.
At least 84 people were injured in Caracas and demonstrator Miguel Castillo died. He was studying communications at Santa Maria University.
"Another Venezuelan that this government robbed of his future," said Stalin Gonzalez, an opposition legislator.
The violence pushed the death toll to at least 38 in more than a month of street protests and political turmoil following the Supreme Court's decision to strip congress of its last powers.
The decision was later reversed amid international criticism but protesters have vowed to stay on the streets.
Demonstrators say President Nicolas Maduro's socialist government has become an authoritarian regime responsible for triple-digit inflation, widespread food and medical supply shortages and soaring crime.
Mr Maduro has dismissed the opposition movement as a violent, far-right effort intent on removing him from power.
Protesters were marching in central Caracas and chanting: "Who are we? Venezuela! What do we want? Freedom!"
Militiamen approached, all dressed in dark colours with pieces of cloth covering their faces. About three carried guns.
The protesters fled, screaming in fear. Opposition leaders have blamed armed pro-government groups known as "colectivos" for a number of protest deaths.
Even though one of the militiamen fired into the air, no one was hit.
Along Caracas's main highway, state security forces used tear gas and water to disperse demonstrators, who threw missiles in their direction.
More than 1,300 people have been detained in the unrest, not including 250 civilians who have been presented before military tribunals.
Mr Maduro is vowing to resolve the crisis by holding a special assembly to rewrite the nation's constitution, though opposition leaders have refused to participate.