Manmohan Singh , the Prime Minister of India , has flown back to Delhi on hearing that massive bomb blast has shocked the capital. Prime ministers office , in a statement , said that India will not bow to Terrorism. On arriving at Kolkata from Agartala the Prime Minister was apprised of the blast and he cancelled his scheduled programs in West Bengal. He flew back in his special plane. The Prime minister on arrival in Delhi is expected to visit the victims and review the law and order situation. Following this attack in which at least 50 people are fear dead, a strict security measure has been taken in Kolkata too when Diwali and Eid are going to be observed within days.