The deceased has been identified as M Rakesh Kumar of East Marianathapuram.
UK police probe video in which man says he will assassinate British Queen to avenge Jallianwala Bagh
Scotland Yard officers were investigating the video reportedly linked to the intruder armed with a crossbow arrested at Windsor Castle on Christmas Day.
Police have named the bomber as 32-year-old Emad Al Swealmeen, who came to Britain as an asylum-seeker several years ago and had converted to Christianity in 2017.
The blast involved a taxi and a male passenger of the car was declared dead at the scene outside Liverpool Women's Hospital and is yet to be formally identified.
Wayne Couzens, 48, who served with the elite diplomatic protection unit of London's Metropolitan Police, admitted her kidnapping, rape and murder in July.
Wayne Couzens previously admitted kidnapping and raping Sarah Everard, a marketing executive who went missing on March 3.