French police on Friday released the 30-year-old woman who caused a massive pileup during the first day of the Tour de France last weekend. She will have to stand trial in October.

The woman, whose name has not been released, was arrested on Wednesday and questioned in connection with the incident caused by a large cardboard panel during the first stage of the race in northwest Brittany.

The Brest prosecutor’s office said she will be in court on 14 October, where she could be charged with negligence and unintentional bodily harm.

Dressed in a bright yellow jacket, she was seen on Saturday showing cameras a handwritten cardboard banner that read “Allez Opi-Omi!” (“Let’s go, grandpa and grandma!”) in front of the cyclists.

German cyclist Tony Martin, riding out of the tightly packed peloton, could not avoid a collision with the sign. The resulting pile-up caused a five-minute delay as cyclists had to separate from their bikes.

Dozens of cyclists suffered from cuts and bruises, and one broke his arm. This sparked a debate about spectator safety and behaviour at the Tour de France, where fans are allowed to stay along the roads.

The woman told investigators she was ashamed of her “stupidity” and concerned about the public interest in her case.

The Tour de France, which had filed a complaint against the woman, said on Thursday it was withdrawing the complaint “to put minds at rest.” The second complaint was filed by the Swiss cyclists’ association Cyclistes professionnels associés, Brest prosecutor Camille Miansoni said.