BJP president Amit Shah Tuesday launched a scathing attack on the Trinamool Congress government in West Bengal, and charged Chief Minister Mamata Banerjee of jeopardising national security for the sake of vote bank.Addressing a Bharatiya Janata Party rally in Burdwan where an explosion killed two Bangladeshi militants, Shah said the blast took place only because the Trinamool was sheltering Bangladeshi infiltrators."When the Narendra Modi government has taken the country towards the path of development, the Trinamool government has taken Bengal backwards. While the BJP wants to work for the development of Bengal, Mamata ji doesn't allow us to do that," he said.The Burdwan blast was an example of the Trinamool's vote bank politics and the incident would not have taken place if the Trinamool had properly investigated a blast in Kolkata a year before the Burdwan explosion, he added.