Stephen Blessy News Today : Breaking News, Live Updates & Top Stories | Vimarsana

seoul with what has become a makeshift memorial there, ivan. are you learning any more about what triggered the surge? >> reporter: just a sheer mass of humanity. many, many young people, thousands of them that gathered steps from where i'm standing right now to celebrate halloween, to drink, tricked out in costumes and it turned into a nightmare. i'll get out of the way so you can take look at this very somber, very sad scene here. people have been laying flowers and lighting candles, handwritten notes to some of the 154 mostly very young victims of this terrible catastrophe. i've s...

>> reporter: the korean government has declared a week of mourning. most of the victims were in their 20s. the government says five her high school students, one was a middle school student. i'll point you here. this is a 20-year-old american exchange student, stephen blessy who was here on his junior semester abroad. >> junior year in college. just devastating. ivan, where does the investigation go from here? >> reporter: well, the police have come out, and they say that they simply didn't have a guidebook or a manual for a gathering of this kind without a single organizer. they had anticipat...