Progress is being made....
The investigation is still ongoing....
The attacker, who was shot dead, has now been identified....
He was described as being 'cowardly'....
He had been catfishing young girls on Snapchat....
More and more tributes are continuing to flood in....
He mocked his victim while she bled from her head....
Police are still appealing for information...
15 arrests have been made so far....