RIO DE JANEIRO — A much-hyped protest for the right to go topless on Rio de Janeiro’s beaches fell flat Saturday when only a handful of women bared their chests for the movement.

More than 100 photojournalists stampeded across the sands of Ipanema beach when the first woman took off her bikini top to flout Brazilian law. Just three or four other women joined in.

“A breast isn’t dangerous!” said Olga Salon, a 73-year-old Rio native, as she stripped off her black tank top. “It’s a false-Puritanism and indicative of our macho culture that we have a law forbidding that a woman can go topless.”

Internationally, Brazil has a reputation as a nation of liberal sexual mores, where nudity is not only tolerated but enthusiastically embraced during Carnival parades.

The hundreds of thousands of foreigners who’ll descend on Brazil for next year’s World Cup and the Olympics two years later will indeed see the famed “dental floss” bikinis that expose the wearer’s rear end.

But under Brazil’s penal code, which dates back to the 1940s, female toplessness is an “obscene act,” punishable by three months to a year in prison, or fines. Even the law’s critics admit few are prosecuted.

Women going topless on any of the city’s beaches are almost guaranteed quick responses, both from patrolling municipal guards and fellow beachgoers.

Saturday’s protest is the latest chapter in a debate over just how much skin is too much on Rio’s beaches. Protest organizers told media they were responding to a November incident in which actress Cristina Flores was set upon by municipal guards after she removed her shirt during a photo shoot on Ipanema beach.

“They came at me immediately and there were three of them, more than one per breast,” the 37-year-old Flores said with a laugh earlier this week. “They were shouting, ‘Put your shirt on, put your shirt on’ as if a bomb were going off if I didn’t.”

Flores immediately complied but said she was shocked by the violent reaction and threat of jail time.

“I didn’t even know it was illegal when I did it,” she said. “But if the Brazilian constitution guarantees gender equality, why should men be able to walk around without a shirt, while when we do it it’s seen as an act of provocation?”