By Sarah Dilorenzo, AP

SAO PAULO — When completed in 2015, the mayor’s office hailed the graffiti panels along Avenida 23 de Maio as Latin America’s largest open-air mural — 70 works of street art stretching for more than 3 miles (5 kilometers) along a boulevard connecting a well-to-do district with the city center.

Then this January, they were painted over.

It wasn’t done by vandals or other graffiti artists, as often happens with street art, but by sanitation workers acting on the orders of Sao Paulo’s new mayor, Joao Doria, a millionaire businessman and former host of “The Apprentice Brazil.” The mayor even donned a pair of orange coveralls and wielded a spray gun to put a thin layer of gray paint over the murals — angering people who considered the paintings part of the city’s cultural heritage and sparking a debate about what is art and what should be protected.

Removal of the murals was among the first acts of Doria’s “Pretty City” campaign: a traveling circus of street cleaners and maintenance workers who install new trash cans, plant trees, pick up garbage and cover up graffiti around Sao Paulo every weekend. Doria says the goal is not just to clean up Sao Paulo but to restore Paulistanos’ pride in their hometown.

Street Art Style Many in Sao Paulo have cheered the campaign for aiming at a widely despised style of street art known as “pichacao” — a generally monochromatic, rune-like calligraphy covering buildings across the city. Doria’s administration has increased fines for pichacao, is installing cameras to catch practitioners, and encourages everyone, especially taxi drivers, to report it.

But most Brazilians make a distinction between pichacao — derived from the Portuguese word for tar — and the colorful and pictorial street paintings they call “graffiti.” The latter are largely tolerated, often celebrated and widely seen as linked to Sao Paulo’s urban identity.

Many considered the murals on 23 de Maio a showcase for Brazil’s vibrant graffiti art, and Doria’s decision to paint over all but a few touched a nerve about what can be lost when cities revitalize blighted areas.

Some of Doria’s critics tie the cleanup campaign to other parts of his business-oriented agenda: a privatization plan to sell off city stadiums and open bids for concessions in public parks as well as an effort to revitalize the dilapidated downtown, an important canvas for pichacao.

“This is not just about a fight against pichacao,” said Marcio Siwi, a doctoral candidate at New York University who studies art, architecture and urbanism in Sao Paulo. “This is bigger than that. This is about bringing revenue into the city in a way that’s very controversial.”

Other cities have waged similar campaigns. The mayor of Lima, Peru, in 2015 ordered the painting over of murals authorized by his predecessor and was showered with complaints from artists and architects who said the murals had reclaimed a dilapidated area. New York has largely won its war to banish the graffiti that once covered subway cars — an art style several graffiti artists in Brazil have cited as inspiration — but many New Yorkers protested when the owner of a Queens warehouse known as 5Pointz, which had become a shrine to graffiti art, painted over its murals in 2013 ahead of its demolition.