Deadly violence erupted in Venezuela as voters went to the polls in the country's controversial election that will see a new assembly created with powers to rewrite the constitution.

A candidate in Venezuela's southeastern town of Ciudad Bolivar, 39-year-old lawyer Jose Felix Pineda, was shot dead by assailants who broke into his home overnight, prosecutors said.

The opposition is boycotting Sunday's vote, with all 5,500 candidates for the 545 seats in the constituent assembly supporters of President Nicolas Maduro.

The vote's success will be measured by turnout and the Government is encouraging participation with tactics including offering social benefits like subsidised food to the poor and threatening state workers' jobs if they don't vote.

The run-up to the vote has been marked by months of clashes between protesters and the government, including the fatal shooting of a 61-year-old nurse by men accused of being pro-government paramilitaries during a protest at a church.

Mr Maduro asked for global acceptance as he cast his vote for an all-powerful constitutional assembly.

President Maduro, widely disliked for overseeing an economic collapse during his four years in office, has promised the assembly will restore peace after months of protests during which more than 115 people have been killed.

Critics say the assembly will allow Mr Maduro to dissolve the opposition-run Congress, delay future elections and rewrite electoral rules to prevent the socialists from being voted out.

The special assembly being selected on Sunday will have powers to rewrite the country's 1999 constitution but will also have powers above and beyond other state institutions, including the opposition-controlled congress.

While opinion polls say a vast majority oppose him, Mr Maduro made clear in a televised address Saturday evening that he intends to use the assembly to govern without limitation, describing the vote as "the election of a power that's above and beyond every other. It's the super power!"