(CNN) -- It's been a month since violent clashes between opposition demonstrators and government forces in Venezuela first grabbed global attention.
Protests rage on, and demonstrators show no sign of backing down.
Medical sources at a hospital in Venezuela's Carabobo state said a student protester and a 42-year-old man were killed in clashes there Wednesday. State media accused violent right-wing groups of attacking a worker's march there. In a Twitter post, state Gov. Francisco Ameliach said a national guard captain had been killed in fighting, which he described as "terrorism."
A government tally released Tuesday said at least 23 people had been killed nationwide and more than 200 others have been injured since protests started. The tally did not specify whether the casualties occurred among demonstrators or government forces, or both.
Student protesters on both sides packed streets in Caracas Wednesday.
State-run VTV showed pro-government demonstrators waving flags with the face of former President Hugo Chavez as they marched. Opposition student protesters also marched in the country's capital, CNN affiliate Globovision reported, calling for the resignation of the government's ombudsman.
Violence surged this week in Tachira state, which borders Colombia. Government forces shot tear gas at opposition barricades there, and a well-known student leader was gunned down Monday.
Daniel Tinoco, 24, was a university student studying mechanical engineering. He died after he was shot in the chest.
Witnesses told CNN en Español that they were at a peaceful vigil with Tinoco in the city of San Cristobal when two white trucks with 10 armed passengers ambushed the protesters and open fire. The witnesses accused government intelligence services of being complicit in the shooting.
Authorities have said they're investigating and denied reports that a government vehicle was involved in the shooting.
The weeks of protests across Venezuela mark the biggest threat President Nicolas Maduro has faced since his election last year. Demonstrators say they have taken to the streets to protest shortages of goods, high inflation and high crime.
Opposition protesters and government officials have traded blame for the violence for weeks.
In an exclusive interview with CNN's Christiane Amanpour last week, Maduro was unapologetic about his government's response to opposition protesters.
Think about what the U.S. government would do if a political group laid out a road map for overthrowing President Barack Obama, Maduro said.
"What would happen in the United States if a group said they were going to start something in the United States so that President Obama leaves, resigns, to change the constitutional government of the United States?" Maduro said. "Surely, the state would react, would use all the force that the law gives it to re-establish order and to put those who are against the Constitution where they belong."
An opposition leader who encouraged protests, Leopoldo Lopez, remains behind bars, facing charges of arson and conspiracy.
"He created a road map to topple the legitimate government," Maduro told CNN last week. "So now he's in jail and he has to go through justice."
But opposition demonstrators have argued that the government's approach of tamping down dissent is anything but just.
"No one accepts a monologue nor impositions from a government that has wanted to resolve the crisis with deaths, injuries, tortures, detentions and prisoners," opposition leader Henrique Capriles Radonski said in a Twitter post Wednesday.
After a meeting in Santiago, Chile, to discuss the crisis in Venezuela, foreign ministers from the Union of South American Nations said they would send a special commission to support and advise a process of peaceful political dialogue in Venezuela.
The group will have its first meeting by the first week in April, the statement said.
The foreign ministers from Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname and Uruguay condemned the recent violence in Venezuela and expressed their solidarity "with the families of the victims, with the people and with the democratically elected government of this sister nation."
In remarks broadcast on state-run VTV Tuesday night, Maduro said he would welcome a delegation from the regional body to help encourage dialogue in Venezuela.
At a U.S. House hearing Wednesday, Secretary of State John Kerry said the U.S. government is prepared to sanction Venezuela if the situation worsens, but he also cautioned that the country's economy is already fragile.
While the United States has voiced its concerns, other countries in the region are "not listening to us, particularly, obviously," Kerry said. The Venezuelan government has continued efforts to blame the United States for problems there, he said, which makes it hard for "us to be able to have the impact we'd like to have."
But still, Kerry said he hoped peer pressure from other South American nations could help resolve the crisis.
"I think the best hope right now is that the efforts of the neighboring countries, who are deeply concerned about what is happening and its impact on the region, may, may be able to encourage the kind of dialogue that could actually pave a way forward," he said. "We've become an excuse. We're a card they play."
CNN's Rafael Romo, Fernando del Rincon and Jose Manuel Rodriguez and journalist Sasha Ackerman contributed to this report.