The Miami Herald reported crowds amassed in Sucre, in eastern Caracas — one of the eight opposition rallying points. City council member Juan Carlos Vidal said violent clashes overnight with police had some protesters wary of taking the street, yet they still seemed to be showing up in force.

The pictures of the crowd at one of the eight locations looks like over 500,000 people. If there are eight such locations then over a million possible a couple of million took to the streets.

US Secretary of State Mike Pompeo warned Venezuela's Nicolas Maduro not to use force against mass demonstrations and urged further international support for the self-declared acting president.

Pompeo demands that the military, whose leadership has confirmed its loyalty to Maduro, protect Guaido, a day after deadly street clashes.

"I reiterate our warning about any decision by remnant elements of the Maduro regime to use violence to repress the peaceful democratic transition," Pompeo says.