(Adds context, demonstrators, defense minister)
By Andrew Cawthorne and Deisy Buitrago
CARACAS, Feb 18 (Reuters) - A student protester died in eastern Venezuela after being hit by a vehicle, the fourth fatality from political unrest over the past week against President Nicolas Maduro's government, residents said on Tuesday.
They said the 17-year-old was struck by a vehicle during a demonstration against the OPEC nation's socialist government late on Monday in the coastal town of Carupano.
That added to three fatal shootings last week during rival rallies in the capital Caracas.
Student-led protests have multiplied across the South American nation of 29 million people since the start of February in the biggest challenge to Maduro since his election last year.
Numbers, though, are small compared to mass social movements in places such as Brazil, Ukraine and the Middle East, and there has been little sign of Venezuelans joining them en masse in the hundreds of thousands seen on the streets a decade ago.
Nor has there been any evidence Venezuela's military might turn against Maduro, the 51-year-old successor to Hugo Chavez.
"The armed forces will always be on the side of justice and development of the fatherland," defense minister Carmen Melendez said. "Every act of violence takes us back to intolerance."
The student protesters are demanding Maduro's resignation and also raising a litany of complaints from inflation and crime to corruption and product shortages.
'HOW LONG THE HATE?'
Local analyst Luis Vicente Leon said the demonstrators must be realistic. "The opposition should be clear that their protest can't be to get rid of a government but rather to demand improved performance," he said.
An opposition legislator and anti-government activists alleged that the dead student in Carupano, Jose Ernesto Mendez, was hit by a government supporter. But there was no independent confirmation or a response from authorities.
"For how long will the hate go on?" Cesar Rincones, a legislator of the opposition Democratic Action party, tweeted.
Residents said three other demonstrators were injured in the melee in Carupano, in Sucre state. One was gravely hurt.
In Caracas, security forces with water cannons and anti-riot gear patrolled the streets on Tuesday morning ahead of marches planned by Maduro supporters and opponents.
Many residents stayed home, fearing more trouble after the daily clashes that have occurred since last Wednesday's fatalities in the capital.
Hardline opposition leader Leopoldo Lopez, 42, has called his supporters out to accompany him in a march on Tuesday.
The U.S.-educated economist Lopez, who has a Masters from Harvard University and is a distant relative of Venezuelan independence hero Simon Bolivar, had been spearheading protests but then disappeared from public view since Wednesday.
In a video posted online, he said he would hand himself over to authorities, who have issued an arrest warrant for him on charges of murder and terrorism tied to the recent violence.
"To those accompanying me, I ask them just to come to one point. Then I will go alone, I will not expose them," said Lopez, who plans to go to the Ministry of Interior and Justice.
RIVAL CARACAS DEMONSTRATIONS
Opposition supporters began gathering in a square of east Caracas from early Tuesday, many wearing the colors of the national flag and carrying anti-Maduro banners.
Maduro has also urged his supporters to flood the streets.
Bus-loads of government supporters or "Chavistas" as they are called after Maduro's mentor and predecessor Chavez, who died last year of cancer, were arriving in central Caracas from before dawn. Many wore the red of the ruling Socialist Party.
Maduro's government has expelled three U.S. diplomats it accused of recruiting university students for the protests. Washington has called that accusation "baseless."
Venezuela's highly traded global bonds, which fluctuate sharply on political tension, are at 18-month lows.
Complaints about acts of violence by both sides have piled up over six consecutive days of confrontations between police and demonstrators. Only 13 students were still reportedly detained after nearly 100 arrests in the past week.
Opposition activists say some of the detained students have been tortured, while Maduro insists police have been restrained in the face of provocation and attacks.
He has, however, publicly criticized the Sebin national intelligence service for having agents in the street and replaced its head on Tuesday. (Additional reporting by Jaczo Gomez and Daniel Wallis; Editing by Daniel Wallis and James Dalgleish)