Rival demonstrations are taking place in Venezuela in response to calls by opposition leader Juan Guaidó and President Nicolás Maduro.
In the capital Caracas, some supporters of Mr Guaidó scuffled with police and were driven back with pepper spray.
Mr Guaidó declared himself interim president on 23 January and has been at loggerheads with Mr Maduro ever since.
Saturday’s protests follow widespread power cuts that have affected much of Venezuela since Thursday.
Mr Guaidó, who leads the opposition-controlled National Assembly, has been recognised as interim president by more than 50 countries. However, Mr Maduro retains the support of the military and close allies including Russia and China.
What is the latest?
On Saturday, police were out in force where the opposition march was taking place in Caracas.
Some protesters pushed against police in riot gear shouting “murderers” and the officers responded by firing pepper spray at them.
Addressing the rally later, Mr Guaidó announced he would embark on a tour of the country and summon all his supporters to attend a mass protest in Caracas “very soon”.
“We are going to come, all of Venezuela to Caracas, because we need all of them united,” he said.
Using a megaphone to be heard above the chanting crowd, he called on his followers to remain “united and mobilised… in the streets”.