Maybe it has. Can't say with certainty because there is a media ban in the affected area. Report are sketchy. Whatever I am writing is based in what I have seen on my visits and extended stays in Kolkata on-and-off.
No one really knows for sure how many Bangladeshis are there in the state, for starters. And political mobilization in Bengal has always been at a totally different level than in other states. You can organize impromptu masses of thousands at an hour's notice, which is a dangerous situation. My friends have stopped going out of the city to their factories or farm houses for the past week or so, because they say the police cannot/will not protect them.
Many of the goons creating trouble have the ruling party's support, so the police may be helpless, really. But I think something more sinister is at play here. It may be the perfect alignment of the state and central government both willing to play with fire to gain from religious polarization and the ensuing violence.
Even if the situation gets out of hand, I think Modi would rather watch the spectacle than do something, as it will help in furthering his own cause. What greater case can be built against Indian Muslims than stories of Hindus being massacred in Bengal? The state may just be caught between two sides both of whom feel they can take advantage of the fallout. If that is indeed so, I think we are in for a whole lot of trouble.