Venezuela votes in tense congressional elections

People in Venezuela are voting in congressional elections
that are seen as the first serious challenge to the governing
socialists in 17 years.
Opinion polls suggest a broad opposition coalition could
capitalise on widespread frustration over food shortages,
inflation and crime.
The governing PSUV, however, retains wide support in rural
areas, and will continue to control the presidency.
Voters will be electing all 167 National Assembly members.
The BBC's Candace Piette says that even if the opposition
Democratic Unity Roundtable captures a majority in the
assembly, its power will be limited.
However, a win for the coalition - which includes centre-left
and centre-right groups - could mark a potential political
shift in the country, our correspondent adds.
The elections are widely regarded as a referendum on
President Nicolas Maduro, the handpicked successor of the
late president Hugo Chavez, and the party's socialist
policies.
The opposition accuse the United Socialist Party of
Venezuela (PSUV) of mismanaging the economy and of
squandering the country's oil wealth.
Mr Maduro says his party defends the interests of ordinary
Venezuelans and wants to complete Mr Chavez's
"Bolivarian Revolution".
"They say they're winning in the polls - it's the same story
of the last 17 years," Mr Maduro said at one election rally.
"Let them win in the polls, we will win in the streets."
Key facts
Polls open at 06:00 (10:30 GMT) on Sunday and close
at 18:00 (22:30 GMT)
Voting and counting is electronic
Exit polls are banned
The only body allowed to publish results is the national
electoral council, the CNE
The CNE will publish the results once there is an
irreversible lead
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Among the concerns are chronic food shortages of staples -
such as milk, rice, coffee, sugar, corn flour and cooking oil.
Mr Maduro has blamed the situation on an "economic war"
waged against his government by the opposition.
The opposition also accuses the government of increasing
authoritarianism.
Earlier this year opposition leader Leopoldo Lopez was given
a 13-year prison sentence for inciting violence - a charge
critics say was politically motivated.
Venezuela has invited election monitors from regional body
Unasur but has rejected those from the Organisation of
American States (OAS) and the European Union.