The four-night festival is illuminating landmarks across the city.
Asylum seeker Alaeldien Ahmed denies murdering father-of-four Anthony Banting in a random attack.
Anthony Small is accused of encouraging acts of terrorism in connection with a video posted online.
Akhtar Javeed, 56, was killed in February 2016 during a botched armed robbery at his warehouse.
Celine Dookhran was found dead in July 2017 at an empty house in Kingston, south London.