The sound of chanting of mantras reverberating in the air during the 'Ganga aarti' in this holy town turned into wails of people with the bang of an explosion on Tuesday evening (December 7). The crowd, including a large number of foreign tourists, was witnessing ceremonial 'aarti' of river Ganga at a ghat here. Soon after it got over and people were getting ready to leave when a loud explosion struck the area. The noise of the blast triggered panic among the people who ran helter skelter for their lives.