Several Spanish cities have witnessed protests after a court ordered the release of five men – known as “the pack” – accused of raping an 18-year-old woman at the bull-running festival in Pamplona.
One protester, 66-year-old Carmen Roman, said it was “a shame these scoundrel rapists get away so easily”.
There were also protests in Bilbao, Vitoria and San Sebastian.
Further demonstrations are expected on Friday outside the justice ministry in Madrid, and in Seville, where the men are from.
The attack is said to have happened at the entrance to an apartment building in July 2016, at the start of the week-long San Fermin festival, which attracts tens of thousands of visitors.
The men, who referred to themselves in a WhatsApp group as the pack, were convicted of sexual abuse in April and sentenced to nine years in jail.
They filmed the incident on their phones and bragged about it on the WhatsApp group.
But they were acquitted of the more serious charge of sexual assault, which includes rape.
That was because the court did not consider the victim to have been subjected to intimidation or violence.
Nationwide protests followed, demanding a change in the law.
During the closed-door trial last year, prosecutors had called for much longer sentences of 22 years and 10 months, arguing that the victim had been subjected to “serious intimidation and it prevented resistance or flight”.
After the men appealed their jail terms, the court in Pamplona ordered their release pending the outcome of the appeal.
The court is due to publish its decision on Friday.
The mayor of Pamplona, Joseba Asiron, said his office would appeal against the decision to release them, saying there was “a growing distance… between society itself and certain decisions taken by the courts”.
An online petition calling for the five to be kept behind bars had garnered more than 500,000 names by midday on Friday.
A spokeswoman said while the Spanish government respects the judges’ decision, it “echoes people’s alarm in Spain and that of women in particular”.
The men are all in their late 20s.
One of them used to be in the army, while another is a guardia civil policeman.
Several are “ultra” or hardcore supporters of FC Sevilla.