Venezuela upped pressure on the opposition Wednesday after weeks of protests, arresting two mayors including one in the town where they started and seeking a probe of a prominent anti-government lawmaker.
Authorities said the death toll from the protests rose to at least 30 after a policeman died trying to break up a protest in the western city of San Cristobal, where the demos began February 4.
They later spread to Caracas and many other cities, although they are now losing intensity.
But after days of relative calm, students called for more protests Thursday in a show of solidarity with the mayors.
President Nicolas Maduro's government has been the target of daily protests fueled by public anger over violent crime, inflation, shortages of such basic goods as toilet paper and further stoked by often heavy-handed police tactics.
It is all happening in the country with the world's largest proven oil reserves.
Venezuela's top opposition leader, Henrique Capriles, whom Maduro beat in last year's presidential election, said Maduro is "pouring gasoline on the fire, and he and only he will be responsible for whatever situation develops. Everyone should know that".
Interior Minister Miguel Rodriguez said San Cristobal Mayor Daniel Ceballos has been detained on charges of fueling "civilian uprising" and "supporting" violence in his city in the western state of Tachira.
Prosecutors "issued an arrest warrant... for (fomenting) civilian uprising," which the Bolivarian Intelligence Service carried out, Rodriguez said on state television VTV.
"This is an act of justice... He has fostered and aided all the irrational violence first unleashed in the city of San Cristobal."
Later, the Supreme Court said Enzo Scarano, mayor of the northern town of San Diego, had also been arrested and removed from his job. He is accused of "defiance" in his official duties.
Ceballos is the second leader of the opposition group Popular Will detained over the deadly protests, the biggest challenge yet to Maduro's elected socialist government.
The group's leader Leopoldo Lopez has been detained for over a month in a military facility near Caracas.
In Caracas, Congress voted to request a probe of prominent anti-government legislator Maria Corina Machado on suspicion of "instigating delinquency, treason, terrorism and homicide" stemming from the protests.
Pro-government legislators presented tapes of Machado's telephone conversations as the basis for a probe. Her lawyers called the taping illegal.
If prosecutors do request a probe, they will have to go to the Supreme Court because Machado has immunity as a lawmaker.
She fired back on Twitter that "if they think that by threatening me and invading my immunity they are going to silence me, they do not know me".
Machado, 46, has joined Lopez at the forefront of calling for street protests to force the departure of Maduro, the handpicked successor of the late populist icon Hugo Chavez, who died last year of cancer.
Elected in December, Ceballos says university students in his city who led protests against the government have been unjustly targeted, with at least one killed.
Maduro contends the protests are part of a "fascist" right-wing, US-backed plot to destabilize his year-old government.