Lethal police crackdowns and mass arrests are oppressive tools that Sheikh Hasina has used throughout her 15 years in power. Not only did Hasina deploy her overwhelming security forces to break into homes, interrogate families, and round up tens of thousands, but her ruling party also unleashed its violent youth wing to help terrorize protesters. Hasina is perfectly fine with violence so long as it's perpetrated by her supporters.
Hasina and her party have remained in power since 2009 not through violence but through elections. Due to this fact, the opposition BNP Party, often backed by Western powers, has taken advantage of genuine student protests and turned them into riots to destabilize the country and call for new elections. Hasina is no stranger to political upheaval — given her entire family was assassinated in 1975 — so hopefully she can fight through yet another era of inorganic chaos.