“There’s a great deal of freedom here to do what we want,” said Yaneth Rivas, 27, a member of the same street-art brigade as Mr. Zerpa, called the Communications Liberation Army. Her work, mainly posters placed at bus stops, is more nuanced than Mr. Zerpa’s. She explores, for instance, the polarization of Venezuelan society in one image showing two policemen from different districts of Caracas pointing guns at each other.

Their groups, together with other street-art brigades, were created over the past year or so by the Ministry of Communes. Some groups remain part of the ministry, like Guerrilla Communications, which offers graffiti and stencil workshops around the city.

Others, like Communications Liberation Army, operate somewhat autonomously but still get material like spray paint from the government.

Image The more overtly political images tend to glamorize President Hugo Chávez’s Bolivarian revolution, and his demonization of Washington is a favorite subject. Credit... Meridith Kohut for The New York Times

“These groups share the objective of reclaiming public space and turning it into a kind of street periodical that can be constantly renewed and painted over to get their message out,” said Sujatha Fernandes, a sociologist at Queens College in New York who has written a book on urban social movements in Venezuela.

Not everyone putting up images on walls here draws support from the government. Saúl Guerrero, a stencil painter who ranks among the city’s most prolific street artists, has painted dozens of melancholic portraits of people around the eastern districts of Caracas, signing them with the nom-de-plume “Ergo.”

Mr. Guerrero, 29, an anthropologist and aid worker who spends part of the year in Africa, opted to forego sharp political statements for simple portraits, often of young Africans or of worn-out faces that reflect a life of destitution. He painted dozens of them on walls and telephone boxes in Chacao, a relatively prosperous municipality here.