(New throughout, updates with third death, adds comment from Maduro)
By Andrew Cawthorne and Diego Ore
CARACAS, March 12 (Reuters) - Protesters battled soldiers in the streets of Caracas again on Wednesday as three more fatal shootings raised to 25 the death toll from a month of demonstrations against Venezuela's socialist government.
Thousands of supporters and foes of President Nicolas Maduro took to the capital's streets for rival rallies marking a month since the first bloodshed in the recent unrest around the South American OPEC nation.
Trouble began when National Guard troops blocked opposition marchers from leaving Plaza Venezuela to head to the state ombudsman's office. Students threw stones and petrol bombs while security forces fired tear gas and turned water cannons on them.
Reuters witnesses saw dozens of people leaving injured.
Elsewhere, in central Carabobo state, a student, a middle-aged man and an army captain were shot dead in the latest fatalities from now-daily clashes around the South American nation of 29 million people.
Opposition activists blamed armed government supporters for shooting the student near his home in Valencia city, but the state governor said the shot came from snipers among protesters.
A 42-year-old man died during the same disturbances, shot while painting his house, the local mayor said. In the third killing, an army captain died from a gunshot during a clash with "terrorist criminals", government officials said.
Maduro's government has declared victory over an attempted "coup" against the 51-year-old former bus driver who won election last year to succeed the late Hugo Chavez.
Student radicals have vowed to continue the "Venezuelan Spring" protests. But despite the bloodshed and drag the actions have had on the county's troubled economy, Maduro appears to be in little danger of being toppled.
"I'm going to take drastic measures against these sectors who are attacking and killing the people," a furious Maduro said in a speech to the nation as night fell.
VICTIMS ON BOTH SIDES
In the first deaths on Feb. 12, two opposition supporters and a pro-government activist were shot dead in Caracas, galvanizing the fledgling protest movement and sparking clashes in Caracas and some western Andean cities.
The 25 people killed include victims on both sides.
"The opposition are causing all the violence. They should think a bit smarter. The street barricades make no sense, they just bring violence," said government supporter Marcos Alacayo, 46, among hundreds of 'Chavistas' at a square in east Caracas.
"They're trying to make out the nation is in a bad state, but that just isn't true. More people have access to healthcare, education and good food than ever. That's what they don't understand. Before Chavez, no one had what we have now," added Alacayo, who works for a state-run higher education program.
Of the more than 1,300 people arrested since anti-government demonstrations began at the start of February, 92 are still behind bars, according to the government.
Those held include 14 security officials, some of whom are implicated in the deaths of two of those shot in the Feb. 12 rallies. More than 300 people have been injured in the unrest.
"Today we're marching to denounce the repression. There can't be impunity. Why do they attack us when we are demonstrating freely? The security forces are bowing to a political ideology when their duty is to protect the people," said law student Agnly Veliz, 22, at the opposition rally.
Veliz said she was at the fateful Feb. 12 rally and has been protesting every day since then. "What's the point of graduating while the country is in chaos? If I lose the year but help to achieve a better Venezuela, then it's worth it."
Although their movement is smaller than those in Brazil, Ukraine and the Middle East, the protesters in Venezuela share a similarly amorphous list of grievances and causes.
Some want Maduro out now. All complain about crime, inflation and shortages of basic goods. Demands to free detainees, especially hardline opposition leader Leopoldo Lopez, have become an increasingly loud cry on the streets.
"Look what they're doing to us," said student Pedro Romero, showing an injury on his leg from a gas cannister in the Caracas clashes. "That's how they treat the future of this country."
As dusk fell, protesters moved to the capital's Plaza Altamira and fighting continued with security forces.
Some demonstrators broke windows and vandalized a local office block, hauling chairs and desks outside to sit in the street as piles of rubbish burned behind them.
The protests have wrong-footed the moderate leadership of Venezuela's opposition coalition, including two-time presidential candidate Henrique Capriles, who lost to Maduro by just 1.5 percentage points in last year's vote.
His strategy had been to work patiently in grassroots communities while waiting for the next electoral opportunity, parliamentary elections in 2015, but now firebrand opposition leaders and students are taking the lead.
Other Latin American nations, though deeply worried, have taken a relatively low-key approach to Venezuela's crisis.
Leftist allies have backed Maduro's right to defend himself against "coup plotters" while more conservative governments have urged dialogue but in moderate terms.
Maduro broke diplomatic ties with Panama after it pushed for a meeting of the Organization of American States to discuss Venezuela. Caracas views the OAS as a U.S. pawn.
Foreign ministers from South America's Unasur group of governments met in Chile on Wednesday to discuss Venezuela.
U.S. Secretary of State John Kerry said Venezuela's neighbors should take the lead in helping mediate the situation, and rejected Maduro's repeated accusations that Washington was deliberately stirring up trouble against him.
"We've become an excuse. We're a card they play," Kerry told a U.S. House of Representatives committee. "And I regret that, because we've very much opened up and reached out in an effort to say, 'it doesn't have to be this way'."
Oil exports, which provide 95 percent of Venezuela's revenues, remain unaffected by the crisis. (Additional reporting by Girish Gupta and Eyanir Chinea in Caracas, Fabian Cambero in Santiago and Jim Loney in Washington; Editing by James Dalgleish and David Gregorio)