Opponents of Venezuela's leftist government marched towards jails on Friday demanding the release of opposition leaders they say are being unjustly held as political prisoners in the country's deadly crisis.
It was the latest in a month of demonstrations that have left 28 people dead in clashes between riot police and anti-government protesters, according to prosecutors.
The center-right-led opposition is demanding elections to remove President Nicolas Maduro. It blames him for an economic crisis that has caused food shortages.
The key rally on Friday targeted Ramo Verde prison near Caracas, where the most prominent of the prisoners, Popular Will party leader Leopoldo Lopez, was being held after his arrest in 2014.
Lopez was sentenced to 14 years on charges of inciting violence during deadly riots that year.
A lead prosecutor in the case later alleged irregularities in his conviction.
Lopez's wife Lilian Tintori has became one of the international faces of Venezuela's political crisis, traveling to meet with foreign officials to raise awareness of her husband's fate.
"We do not want confrontation, violence or gunshots," she said, announcing Friday's rally.
"We want solidarity with those who are resisting like Leopoldo. We want a country without dictatorship and without repression."
- March to the jails -
Opposition supporters gathered at various spots in the capital on Friday planning to march to two key jails where their allies are held. Similar marches were called in other cities.
On the road to Ramo Verde, military police mounted a barrier of trucks and metal fencing on Friday.
Attempts by protesters to march towards other sensitive state institutions have erupted into deadly violence over recent days.
Senior opposition lawmaker Henry Ramos Allup said the security forces had orders not to let the demonstrators pass.
"Either we get there or they will repress us, but we are not going to hold back," said Freddy Guevara, deputy speaker of the opposition-held national legislature.
The United States, European lawmakers and other international authorities have urged Maduro's government to free "political prisoners."
The opposition says there are 170 such prisoners.
The government denies they are locked up for political reasons, insisting they were jailed for violent crimes or conspiracies.
A further 1,000 people have been arrested since the latest wave of violence erupted on April 1, authorities say.
Maduro accuses Washington of leading a plot to overthrow him and says the economic crisis is a US-backed capitalist conspiracy.
He has refused to hold a general election before the next scheduled poll due in late 2018.