Venezuela announced in late April that it would be leaving the OAS, which seeks to defend democracy throughout the hemisphere, and its representative was not present at Monday's meeting. Maduro contends the OAS is meddling in Venezuela's domestic affairs, infringing on its sovereignty and trying to remove him from power.
The fiery Venezuelan president is vowing to resolve his nation's crisis by convening a special assembly to rewrite the nation's constitution, while the opposition is demanding an immediate presidential election.
Polls indicate the great majority of Venezuelans want Maduro gone as violent crime soars and the country falls into economic ruin, with triple-digit inflation and shortages of many basic foods and medical supplies.
The wave of protests were triggered by a government move to nullify the opposition-controlled congress in late March, but the demonstrations have morphed into a general airing of grievances against the unpopular socialist administration.
As demonstrations take over Caracas almost daily, normal life has continued, but the atmosphere is suffused with uncertainty. At fancy cafes, patrons show each other the latest videos of student protesters getting hurt or defaced statues of the late President Hugo Chavez on their phones. Working class people who have to traverse the capital for their jobs have adjusted their schedules to account for traffic shutdowns and take siestas to wait out clashes between protesters and police.
On Monday, demonstrators assembled a giant rosary with balloons hanging from a Caracas highway overpass. A group of flamenco dancers dressed in black performed for the crowds. Others simply sat and held signs declaring their resistance.
Former presidential candidate Henrique Capriles said the opposition would take its protests "to another stage" as Maduro continues his push to rewrite the nation's constitution.
"We are against this fraudulent process," Capriles said on his radio broadcast.
Tarek William Saab, the national ombudsman, whose job is to protect citizens' rights but who has been tagged the "dictator's defender" by the opposition, said on Twitter that he was pressing for an exhaustive investigation into Alviarez's death Monday to determine who was responsible and ensure they are held accountable.
Maduro blames the opposition for the violence, claiming its leaders are fomenting unrest to remove him from power. The opposition maintains state security and civilian-armed pro-government groups known as "colectivos" are responsible for the bloodshed.
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