VOICED : Oposicion venezolana exigio revocatorio en la calle bajo amenaza

The Venezuelan opposition protested to demand the activation of a recall referendum against President Nicolás Maduro. They urged the electoral authority to respond promptly, warning of potential unrest due to public impatience. Opposition leaders attempted to deliver a document to the National Electoral Council but were blocked by police. The document requested the final step before the referendum, which requires 20% of voter signatures. The government accused the opposition of fraud in collecting signatures. The opposition aims for the referendum before January 10, 2017, to trigger elections if Maduro loses; otherwise, the vice president would complete the term.

What did the leaders of the Mesa de Unidad Democrática attempt to do at the National Electoral Council?

What is the significance of the 20% mentioned in the context of the referendum?