The Met said no arrests had so far been made.
The largest crowd by far was made up of lawyers in starched collars, white shirts, and black suits.
There is broad consensus that the commitments that have so far been made are not yet adequate to meet the 2C limit.
Wang Nai'ang, also of Lanzhou University, says precise calculations are difficult because of the vagueness of the plans that have so far been made public.
But a report submitted by the committee and accepted by the government has not so far been made available by the agriculture ministry.
Tsang said on Wednesday that a motive had yet to be established and that no link had so far been made between Lau's journalism and the attack.
Despite theories that a bomb may have been smuggled on board, no claim of responsibility has so far been made by Islamic State or other terrorist groups.
According to the ministry, more than £21m has been saved by closing the courts and £14.5m has so far been made from the sale of the buildings.
There have been negotiations to bring on board another gaming partner, although no announcement on a deal has so far been made.
