The Mamata Banerjee government is battling its latest challenge in the hills of West Bengal. Protests started in Darjeeling last week over fears that the state government was forcing the Bengali language on schools in the hills. Even the army was deployed after stone-throwers clashed with the police. The West Bengal government has clarified that Bengali would not be compulsory from Class 1 to 10 in schools in North Bengal. But the protest has escalated into a demand for a separate state, Gorkhaland. What started out as an education policy issue has turned into a political challenge for Ms Banerjee.