Police investigating the murder of Kevin McDaid in Coleraine in Co Derry on Sunday evening have made another arrest.
A 33-year-old man was detained in the town this morning.
11 people are now being held in connection with the killing.
Mr McDaid, 49, was attacked by up to 40 men who entered a mainly Catholic housing estate after Rangers beat rivals Celtic to the Scottish Premier League title.
A second man, Damien Fleming, 46, is fighting for his life in hospital after being assaulted during the same disturbances.
Mr McDaid's protestant wife Evelyn was also attacked when she tried to save him. After a beating she was left with two black eyes and covered in cuts and bruises.
PSNI Assistant Chief Constable Alastair Finlay said: 'There is no evidence this was anything other than a maverick group of yobs. This group made their way down from a pub intent on violence.'
The political representatives of the UDA - the Ulster Political Research Group - issued a statement in which it condemned the murder and those who would seek to cause community tensions.
Mr Finlay said there were tensions in the wake of Rangers sealing the title and people in the Catholic area believed there was to be some sort of parade and 'exhibitions of triumphalism' by the loyalist community.
'In response there was a building of barricades to keep them out and a raising of flags,' he said.
'We achieved, as we understood, a settlement where the barricades were removed, indeed Kevin McDaid was part of the removal,' the Assistant Chief Constable said.
