UPDATE 2-Anti-Maduro strike paralyzes swathes of Venezuela

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CARACAS, July 20 (Reuters) - Many Venezuelan streets were barricaded and deserted on Thursday for a strike called by foes of President Nicolas Maduro to demand a presidential election and the abandonment of a plan for a new congress they fear would institute dictatorship.

From the Andes to the Amazon, many businesses shut as the majority-backed opposition staged a 24-hour shutdown from dawn in a civil disobedience campaign it is dubbing "zero hour" to try to end nearly two decades of Socialist Party rule

"We must all do our best to get rid of this tyrant," said Miguel Lopez, 17, holding a homemade shield emblazoned with "No To Dictatorship!" as he manned a roadblock on a Caracas thoroughfare that was devoid of traffic.

Many private transport groups heeded the strike call, while students, neighbors and activists hauled rubbish and furniture into streets to form barriers.

In some places, however, such as the poor Catia and January 23rd neighborhoods of Caracas, streets and shops were still buzzing.

In scattered clashes, security forces fired tear gas at protesters manning barricades. Youths shot fireworks.

Four months of anti-government unrest have killed about 100 people, injured thousands, left hundreds in jail and further damaged an economy in its fourth year of a debilitating decline.

Clashes have occurred daily since the opposition Democratic Unity coalition and a self-styled youth-led "Resistance" movement took to the streets in April. In the latest death, a man confronting protesters was burnt to death this week in the northern coastal town of Lecheria, media and authorities said.

Leaders of Venezuela's 2.8 million public employees said state businesses and ministries remained open on Thursday.

"I'm on strike 'in my heart' because if we don't turn up, they will fire us," said a 51-year-old engineer at state steel plant Sidor in southern Bolivar state, waiting at dawn for transport provided by her company.


No disruptions were expected at oil company PDVSA which brings in 95 percent of Venezuela's export revenue.

"The Constituent Assembly is going ahead!" PDVSA president Eulogio Del Pino said on state TV, surrounded by red-shirted oil workers in Monagas state chanting "they will not return" in reference to opposition aspirations to take power.

Some Venezuelans grumbled the opposition action would cost them money and prevent them seeking food at a time of extreme economic crisis and hardship in the OPEC nation.

"How can I eat if I don't work?" said Jose Ramon, 50, chopping bananas and watermelon at his fruit stall in a market in the Catia district.

With Venezuela already brimming with shuttered stores and factories amid a blistering four-year recession, even a successful strike would have limited financial impact.

Four hours into Thursday's action, it was looking more successful for the opposition than a similar action last year, which had a lukewarm response after the government threatened to seize closed businesses.

Maduro also faces widespread foreign pressure to abort the Constitutional Assembly, which could rewrite the constitution and supersede other institutions. Officials say it will replace the current opposition-led legislature.

U.S. President Donald Trump weighed into the dispute this week, threatening economic sanctions if a July 30 vote for the assembly goes ahead. The opposition is boycotting the vote, whose rules seem designed to guarantee a government majority despite its minority popular support.

Recalling a 36-hour coup against his charismatic and far more popular predecessor Hugo Chavez, the Venezuelan president has said his foes are seeking to oust him by force.

As well as a presidential election, Venezuela's opposition is also demanding freedom for more than 400 jailed activists, autonomy for the legislature and foreign humanitarian aid. (Additional reporting by Andreina Aponte, Corina Pons in Caracas, Franciso Aguilar in Barinas, Anggy Polanco in San Cristobal, Maria Ramirez in Ciudad Guayana; Editing by W Simon)