West Bengal Chief Minister Mamata Banerjee on Wednesday wrote letters to top Opposition leaders, calling on them to unite against the BJP and defend democracy in India. She elaborated on the Centre's 'interference' in the functioning of non-BJP state governments by using Governors and probe agencies like the CBI and ED. Now, BJP chief Jagat Prakash Nadda attacked on Mamata and said it was an attempt to "save her sinking ship" in the West Bengal assembly polls. Watch the video.