(Adds arrests, background on vote)
CARACAS, July 27 (Reuters) - Three people have been killed in clashes between Venezuelan security forces and protesters during an opposition-led strike against President Nicolas Maduro that entered a second day on Thursday.
At least 106 people have died in total during anti-government unrest convulsing the South American OPEC nation since the opposition launched protests in April demanding elections to end nearly two decades of socialist rule.
Many streets around Venezuela remained barricaded and deserted during the second day of an opposition-led shutdown.
Plenty of rural areas and working-class urban neighborhoods were bustling, however, as the 48-hour strike call appeared less massively heeded than a one-day shutdown last week.
"People are working out of necessity," said coffee seller Jose Vazquez, 46, in Caracas though he had fewer customers than usual and there was little traffic on the streets around him.
The strike aims to pressure Maduro into cancelling a controversial vote for a new congress at the weekend.
Adversaries say the ruling Socialist Party wants to consolidate dictatorship with a sham vote for the super-congress that will have the power to rewrite the constitution and shut down the existing opposition-led legislature.
The international community has broadly condemned the vote, and the United States on Wednesday announced sanctions against 13 current and former officials for corruption, undermining democracy, and participating in repression.
Maduro says he is going ahead with Sunday's election for the Constituent Assembly as the only way to empower the people and bring peace to Venezuela.
The Venezuelan prosecutor's office said on Thursday that a 23-year-old man was killed in western Merida state and a 16-year-old boy died in the poor Caracas neighborhood of Petare during clashes on Wednesday.
That added to the previously announced death of a 30-year-old man, also in mountainous Merida state.
More than 170 people have been arrested during the strike so far, a local human rights group said.
Government officials and candidates for the Constituent Assembly were winding up campaigning on Thursday, with a rally planned for Caracas later in the day to be attended by Maduro.
Voters on Sunday will choose 364 constitutional representatives distributed across municipalities and state capitals and another 181 "sectoral" candidates from demographic groups ranging from students to farmers and fisherman.
The opposition Democratic Unty coalition is boycotting the vote. They say the use of sectoral candidates, who had to collect signatures and file them to the government-leaning elections council, was a way to weed out anti-government aspirants.
Critics also note the lopsided representation of rural areas, where the Socialist Party has historically been strongest, at the expense of the opposition-leaning cities.
The country's least-populated state of Amazonas will elect eight representatives to the assembly while the capital of Caracas will choose only seven, according a document about the vote posted on the National Electoral Council's website.
State demographics agency INE data shows Amazonas having a population of 188,000 and the municipality of Caracas 2.1 million. (Additional reporting by Brian Ellsworth; Writing by Andrew Cawthorne; Editing by W Simon)