Germany held a memorial service Saturday for the victims of the Love Parade techno music festival, where 21 people were crushed to death and 500 injured in a tunnel that was the only entrance to the event. The memorial at Salvator Church, which opened with somber organ music, was shown on screens in a football stadium and a dozen other churches in the western city of Duisburg. Several TV stations carried the service live, and flags across the country flew at half-mast. Chancellor Angela Merkel and President Christian Wulff were at the event. Family members of the victims also attended. The 21 people who died were aged 18 to 38 and included foreigners from Spain, Australia, Italy, Bosnia, China and Holland. The governor of the western state of North Rhine-Westphalia - where Duisburg is located - also gave a speech. Visibly shaken, Hannelore Kraft talked about the many partygoers who survived the mass panic. Her own son, 17-year-old Jan, also attended the Love Parade, but was not injured. For several hours after the tragedy, the governor was not able to contact him because the cell phone system in Duisburg had collapsed. “There are many thousands who survived but whose souls were injured,” Kraft said. “They are suffering in silence.” Anger had been building in recent days, with over 250 people protesting in Duisburg on Thursday and demanding the resignation of the city's mayor, Adolf Sauerland. People blame Sauerland and the city's authorities for failing to adequately plan for the event. Private organizers also have come under fire for allegedly trying to squeeze as many as 1.4 million revelers into too small a space and for allowing only one access point onto the festival grounds.