The head of policing at the Champions League final in Paris has apologised for using tear gas on Liverpool fans but said he had no alternative.
Didier Lallement admitted the security operation was “obviously a failure”.
But he defended the tactics he used as chaotic scenes unfolded outside the Stade de France last month, insisting his “red line” was to save lives.
French authorities blamed late arrivals and fake tickets for overcrowding and chaotic scenes before the match.
The fiasco outside the stadium has prompted uproar in France as well as the UK and Spain.
Liverpool fans, including families with children, were tear-gassed and pepper-sprayed outside the stadium by police ahead of the final between Liverpool and Real Madrid on 28 May.
Then as they left the area, some fans were attacked by 300 to 400 local youths, Mr Lallement acknowledged.
“It was obviously a failure, because people were pushed around or attacked even though we owed them security,” Mr Lallement told the French Senate on Thursday.
Using tear gas outside the stadium was the only means they had to get the crowd to move back without charging at them, which would have been “devastating”, he explained. However, if his force had not dispersed the crowd, people could have died in a crush.
“I am fully aware that people acting in good faith, even families, were tear-gassed,” he added. “For this I am very sorry. But there was no other way.”
He said his force was not prepared for the scale of the problem that thousands of fake tickets caused.
Interior minister Gérald Darmanin has come under fire for his own response, blaming the trouble outside the stadium on “massive, industrial-scale” ticket fraud which caused Liverpool fans to turn up en masse.
Mr Lallement said the scale of fake tickets had not been considered ahead of the match. Asked why he had put the number of fake tickets at 30-40,000, the police chief admitted he may have been wrong but that was the number he had estimated at the time.
Liverpool fans have complained of fearing for their safety in the crush, despite arriving hours earlier. But they have also told of local gangs from the Saint-Denis area descending on crowds after the match, stealing phones and watches and threatening them with knives.
