A not so unusual incidence in rest of India, it still bothers me to know that a bunch of tourists were attacked by a convoy of a political party in Sikkim ( http://newshopper.sulekha.com/news/21-bengali-tourists-attacked-in-sikkim.htm ).
Five years back when I was Sikkim, I found it to be a friendly place where people smiled and laughed and took it easy with strangers. Tourism was just opening up and people were finding plenty of employment in being a tour-guide, operator or driver. Life was looking good, and at the same time Sikkim was getting exposed to rest of India.
One of those days, on our way to Yumthang Valley, my jeep driver commented that there was a murder somewhere in Sikkim. "It never used to happen in Sikkim," he told me with a voice of concern. He was probably not talking just about the incident, but about the general mood of change in the mountain state.
Constant exposure to rest of India, influx of people into the region in the form of new industrial setups, educational institutions, tourism and national political parties are probably changing this once quiet region high in the Himalayas slowly. Although I have not heard much of it, there is a good possibility that hoards of backpackers who come here aid proliferation of drugs. Vicinity to Bihar, and a considerable number of people immigrating from the plains would have increased the aggression level of people, resulting in incidences like above. The state's aggressive promotion of tourism and the hurry to be a part of mainstream India may accelerate its fall too.
While Sikkim is still a beautiful country where life is largely peaceful, I see some effort required to keep it this way. May be slow and calculated growth and keeping a tab on immigration would be the way to go.