CARACAS, Venezuela (AFP) — Riot police blocked protesters as thousands of people took to the streets Saturday with tensions rising between opposition leader Juan Guaido and President Nicolas Maduro after crisis-wracked Venezuela emerged from the chaos of an electricity blackout.

Both Guaido and Maduro, who are locked in a bitter power struggle for the right to lead the oil-rich South American nation, had asked their supporters to fill the streets of Caracas and other cities in rival demonstrations.

“We want to march! Yes we can!” shouted opposition protesters as riot police prevented them from accessing the street in east Caracas where their demonstration was due to take place.

Overnight, security services had stopped the opposition from setting up a stage in an avenue where their protest was due to take place.

“They think they can scare us but they will get a surprise from the people in the street,” Guaido tweeted.

“They think they can wear us down, but there’s no way they can contain a population that has decided to end the usurpation,” added the leader of the opposition-controlled legislature, who is recognised as Venezuela’s interim president by more than 50 countries.

Guaido is trying to force out Maduro — whose May re-election he deems illegitimate — in order to set up new elections.

Opposition lawmakers denounced the overnight arrest of three people who were setting up a stage at the opposition rally site.

Maduro has asked his backers to march against “imperialism.”

“We’re continuing the battle and victory over the permanent and brutal aggression against our people,” Maduro wrote on Twitter.

“Today, more than ever, we’re anti-imperialists. We will never surrender!”