More than 400 pairs of red and stained white panties covered the sand of Rio de Janeiros Copacabana beach on Monday as part of a nationwide protest against gender-based violence.

Late last month, images of a 16-year-old girl who was reportedly raped by more than 30 men in a Rio favela circulated widely on social media , galvanizing the debate about sexism and violence in Brazil. Hashtags such as #EstuproNuncaMais (Rape Never Again) and #EstuproNaoTemJustificativa (Rape Can't Be Justified) quickly spread on Twitter.

Brazilians in major cities across the country have taken to the streets en masse to protest the attack and condemn the culture of sexual violence in which it occurred.