Ultimately the authorities were able to catch the crazy man threatening passengers with a knife, but I am not sure what authorities in Seoul can do to prevent crazy people from doing crazy things:
Authorities on Tuesday apprehended a middle-aged man who was alleged to have brandished a 10-inch knife and threatened passengers onboard a subway train in Seoul during morning rush hour.
The suspect, determined later to be a 51-year-old homeless man, was caught more than an hour after the episode, in which he brandished a knife onboard a train on subway line No. 1 around 8:20 a.m., before exiting at Jonggak Station.
No injuries were reported, though the incident highlighted a barrage of loopholes present in subway security systems in the capital, with a population density almost twice that of New York City and where more than 7 million people on average use the trains daily.
Last year, police recorded 3,040 crimes at local subway stations, up 58 percent from the 1,922 cases in 2013.
The most apparent oversight, however, is the lack of security resources and personnel. [Joong Ang Ilbo]
You can read more at the link.











