"I came to march because I believe in this country and I want our youth to have a future; Venezuelans want to stay", said Mercedes Expósito, 53, who told NBC News that people say they want to stay in the marches though they're "choking from the tear gas; they will wait until the government runs out of its bombs".
Marchers in the opposition demonstration in Caracas included Liliana Machuca, who earns about $20 a month holding two jobs teaching literature. Others were allegedly shot by government supporters.
"We don't want confrontation", he said.
Her face was covered in a white, sticky substance to protect herself from the noxious effects of tear gas. Maduro also claimed that armed operatives had been arrested in Caracas hotels, but, as always, was short on details.
Protesters had hoped to converge on the office of the state ombudsman, a guarantor of human rights, but as in previous attempts they were blocked by the National Guard. He says Venezuela's government is not allowing the opposition "to organize in ways that expresses the views of the Venezuelan people".
Venezuela's opposition is reaching out to Wall Street banks to dissuade them from helping the country monetize its $7.7 billion in gold reserves.
The march followed a fortnight of violent protests triggered by a Supreme Court decision in March to assume the powers of the opposition-led Congress - which it quickly reversed under worldwide pressure.
The public prosecutor's office said it was investigating both cases.
They included state workers like Leidy Marquez, who was bused in from Tachira state on the other side of teh country.
Maduro, who says recent protests have been little more than opposition efforts to foment violence and topple his government, has called on sympathizers of the ruling Socialist Party to hold a competing march in Caracas.
Eleven Latin American countries on Monday asked Venezuela to guarantee the "right to peaceful demonstration", lamenting deaths that have already occurred during the protests.
"It is the moment for the armed forces to demonstrate that they are with the constitution and with the people", said opposition congressional leader Julio Borges.
After ongoing reports that Venezuelan security forces used excessive force against peaceful protesters, Argentina, Brazil, Chile, Colombia, Costa Rica, Guatemala, Honduras, Mexico, Paraguay, Peru and Uruguay issued a joint statement calling on the Maduro regime to "to prevent any violence against protesters".
On Tuesday night he activated a military, police and civilian operation called the "Zamora Plan" aimed at combatting a supposed coup attempt - which the president says is being orchestrated by Venezuela's opposition and the United States.
Foreign governments are also warning about the increasingly bellicose rhetoric and repressive stance of the government.
"We are going to bring disarmament and peace", Interior Minister Nestor Reverol told Reuters during one confiscation event.
Mr Maduro this week said he was dramatically expanding civilian militias created by the late Hugo Chavez and giving each member a gun.
The center-right opposition is protesting against moves by authorities to tighten Maduro's grip on power.
In the past, the groups known as collectives have operated like shock troops firing on protesters as security forces stand by. A USA state department official has said that they are concerned with the state of Venezuela's democracy and that the country should continue to talk to the opposition as well as hold elections as soon as possible.
Religion and politics mix as Jakarta votes
The election battle has highlighted the growing strength of hard-line Islamic groups in the world's most populous Muslim nation. Private pollsters, approved by the national elections commission, are tabulating a sample of votes known as "quick counts".