Milan -- Italian police have arrested six men on manslaughter charges for allegedly using pepper spray to carry out thefts at a concert for teens, triggering a stampede that killed six people last year. Authorities announced the arrests Saturday, nearly eight months after a rap concert for teens near Adriatic coastal city of Ancona ended in tragedy on Dec. 8.

The six, all men ages 19-22, were part of a gang based in the northern city of Modena that hit nightclubs in northern and central Italy with the aim of robbing unsuspecting club-goers. They are under investigation for manslaughter and for causing injury to 197 others.

A girl cries as lifeless bodies lie on the ground outside disco Lanterna Azzurra in Corinaldo, central Italy, Saturday, Dec. 8, 2018. A stampede at a rap concert in an overcrowded disco in central Italy killed five young teenagers and a woman who had accompanied her daughter to the event. Bobo Antic / AP

Survivors said panic spread after the pepper spray was unleashed. The victims were five teens, ages 14-16, and a 39-year-old mother who had accompanied her daughter.

Get Breaking News Delivered to Your Inbox

Video at the time showed scores of teenagers rushing out of a door and surging toward a low wall near an exit of the Lanterna Azzurra (Blue Lantern) disco in the central Italian town of Corinaldo, near Ancona on the Adriatic coast. The barrier then appeared to give way and a cascade of teenagers tumbled over it, falling on top of each other.

Many of those who were injured suffered broken limbs and crushing wounds, BBC News reported at the time.