Venezuelan opposition leader and Governor of Miranda state Henrique Capriles (C) recovers from tear gas after clashes with riot policemen during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





Venezuelan opposition leader and Governor of Miranda state Henrique Capriles raises his hands in front of riot policemen during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





Opposition supporters clash with Venezuelan National Guards during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





Opposition supporters clash with Venezuelan National Guards during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





An opposition supporter kneels in front of riot policemen during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





Riot policemen help an injured protester during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





An opposition supporter catches a tear gas bomb during clashes with riot policemen in a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Marco Bello/Reuters)





An opposition supporters holding a sign that reads "I recall" (in reference to the revocatory referendum) shouts during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





Opposition supporters carry an injured man during clashes with riot policemen in a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Marco Bello/Reuters)





Venezuelan opposition leader and Governor of Miranda state Henrique Capriles (C) holds a Venezuelan national flag as he stands next to (centre R) Henry Ramos Allup, President of the National Assembly and Jesus Torrealba, secretary of Venezuela's coalition of opposition parties (MUD), during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





An opposition supporter reacts in front of Venezuelan National Guards in a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Marco Bello/Reuters)





An opposition supporter covers his face from tear gas during clashes with riot policemen in a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Marco Bello/Reuters)





Opposition supporters shout slogans to Venezuelan National Guards through a fence, during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





An opposition supporter shouts towards riot policemen in a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Marco Bello/Reuters)





An opposition supporter sits in front of riot policemen in a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Marco Bello/Reuters)





An opposition supporter stands in front of Venezuelan National Guards in a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Marco Bello/Reuters)





A riot policeman fires into the air during clashes with opposition supporters at a rally demanding a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)





An opposition supporter puts stickers depicting the country's constitution on a Venezuelan National Guard truck during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Marco Bello/Reuters)





An opposition supporter reacts during a rally to demand a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Marco Bello/Reuters)





An injured man lies on the street next to national guard members during a demonstration in Caracas on May 11, 2016. With helmets, shields and bulletproof, military and Venezuelan police vests prevented Wednesday the advance of thousands of opponents who tried to reach the headquarters of the National Electoral Council (CNE), to demand accelerate the process of a recall referendum against President Nicolas Maduro. (Photo by Federico Parra/AFP Photo)