Firstly before you start or spread a new hashtag , change your Facebook filter or some other inane pointless platitude, maybe consider a few things about the situation.
Finsbury mosque actually celebrated the 9/11 terror attack and was the breeding ground of several high profile terrorists.
So quickly this incident was called a terror attack. When muslim terrorists committed attacks recently in England the media was looking for any other term to describe the event.
The man allegedly responsible for the incident was held on the ground and kicked in the head, this is contrary to claims of him being held without injury.
London is now clearly no longer a safe place, and until you can say why you think this is the case without punishment, you are not in a safe place either, as the place where you are in slowly turning into London.
If you mourn for Finsbury, you mourn for the supporters of terrorism, who have themselves just been terrorized.