CHAOS has erupted in western Venezuela during another round of protests against the socialist government, with buildings set afire, tear gas swirling around protesters and at least two people killed.

Thousands hauled folding chairs, beach umbrellas and protest signs on to main roads for a 12-hour “sit-in against the dictatorship,” on Monday, the latest in a month and a half of street demonstrations that have resulted in dozens of deaths.

Protests in Caracas against President Nicolas Maduro remained mostly tranquil, but outside the capital demonstrators clashed with police and national guardsmen. In the western state of Tachira near Venezuela’s border with Colombia, two men were reported dead in separate demonstrations: Luis Alviarez, 18, and Diego Hernandez, 33.

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.

Elsewhere in Tachira, protesters threw rocks and set an armoured truck on fire. Buildings were set ablaze and dozens were injured, including a young woman who stood on the street with her face covered in blood.

In the central state of Carabobo three officers were shot, including one left in critical condition after being struck in the head. In Lara, a vehicle ran over three protesters.

The violence added to a mounting toll of bloodshed and chaos as Venezuela’s opposition vows to step up near-daily demonstrations and Maduro shows no intention of conceding to opposition demands.

More than three dozen people have been killed – including a national guardsman and a police officer – hundreds have been injured and as many as 2,000 detained in nearly seven weeks of protests.

International pressure on the troubled South American nation is continuing to increase, with the Organisation of American States (OAS) voting on Monday to hold a rare foreign ministers’ meeting later this month to discuss Venezuela’s political crisis. The Washington-based group only convenes such meetings to address the most urgent affairs.

“We ask the world to look at what’s happening right now in Venezuela,” opposition leader Maria Corina Machado said after Monday’s violence. “A deranged regime that represses and kills its people.”

In late April Venezuela announced 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 was 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 defaced statues of the late President Hugo Chavez or student protesters getting hurt. 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,” he said on his radio broadcast.