Story highlights The incidents occurred at Schlossgrabenfest

The open air music festival was held between Thursday and Sunday

Berlin (CNN) More than two dozen young women reported they were sexually assaulted at a concert in Germany, authorities said.

The alleged incidents occurred Saturday night at Schlossgrabenfest, an open air music festival near Darmstadt town. The festival ran from Thursday to Sunday.

Police said it's likely the sexual assaults could have happened in other locations as more women emerge in addition to the 26 who've come forward so far.

About 80,000 people attended the concert Saturday and 400,000 over its duration, police said.

Most of the reports were filed by women between ages 16 to 25, said Ferdinand Derigs, a spokesman for Darmstadt police.