Opposition supporters protested in Caracas and other cities, denouncing Maduro for eroding democracy and plunging the oil-rich economy into chaos. Crowds swelled to hundreds of thousands, including Maduro supporters who held a counter-demonstration in the capital at the urging of the president, and clashes were reported across the South American country.
Maduro says that beneath a peaceful facade, the protests are little more than opposition efforts to foment a coup to end socialism in Venezuela.
The dueling marches drew parallels to the clashes between pro and anti-government protesters in 2002 that triggered a brief coup against late President Hugo Chavez.
Carlos Moreno, 18, a student, was on his way to play soccer in Caracas and did not plan to take part in the demonstration when government supporters approached an opposition gathering and fired shots, according to witnesses and a family member. Moreno was shot in the head, they said.
His death means six people have now been killed during protests in Venezuela this month. The opposition blames the deaths on security forces and armed pro-government supporters seeking to spook protesters.
Waving the country's red, yellow and blue flags and shouting "No more dictatorship" and "Maduro out," demonstrators clogged a stretch of the main highway in Caracas. Troops fired tear gas in Caracas neighborhoods, the border city of San Cristobal, the depressed industrial city of Puerto Ordaz, and the arid northern city of Punto Fijo.