BERLIN (AP) — Ten people have gone on trial in Germany on charges related to a deadly mass panic at the Love Parade techno music festival in 2010.

Twenty-one people died on July 24, 2010, in a crush in a packed tunnel that was the sole access point to the music event in the western city of Duisburg, and more than 650 were injured.

The victims included people from Spain, Australia, Italy, Bosnia, China and the Netherlands.

Four event organizers and six city workers went on trial in Duisburg state court Friday on charges including involuntary manslaughter and bodily harm. They are accused of serious planning failures and failing to monitor security properly.

About 65 victims or family members of victims have joined the trial as co-plaintiffs as allowed under German law.