A 25-year-old woman has been arrested by detectives investigating the sectarian killing of Paul McCauley on suspicion of withholding information.
Mr McCauley (29) was beaten by a gang of up to 15 at a barbecue in the Waterside area of Londonderry nine years ago.
He was left in a permanent vegetative state and died last month in a nursing home at the age of 38.
The father-of-one was attacked by a gang as he was clearing up after the meal in the early hours of the morning.
He suffered severe head injuries.
Mr McCauley's family has pursued a long campaign for justice.
The latest arrest takes the total number of people arrested since Mr McCauley died in June 2015 to eight.
The woman has been taken to Strand Road Police Station for questioning.
Detective Chief Inspector Michael Harvey said: "This arrest means that a total of eight people have been arrested since Paul died in June 2015.
"While this woman currently remains in custody, one man has been charged with murder, another will be reported to the PPS, four individuals have been released on police bail pending further enquiries and one man has been released unconditionally.
“Our enquiries into this murder are very much ongoing and I would like to thank those people who have so far come forward since Paul’s death to assist us," he added.