It has been four years since the unforgettably tragic 26/11 terror attack on Mumbai, but the Indian government is yet to gets its hands on the voice samples of the attack's masterminds, who are facing trial in Pakistan. India has filed several chargesheets in connection to the 26/11 attack, but the case put together by security agencies could be much stronger if Indian authorities manage to obtain the voice samples which are the final pieces of evidence in the case.