A leading loyalist from north Belfast has been arrested in connection with four murders in the area dating back to the 1990s.
He was detained at Maghaberry Prison near Lisburn by officers from the PSNI's Historical Enquiries Team.
He is being questioned about the UVF murders of John Harbinson in Mount Vernon in May 1997, Catholic builders Gary Convie and Eamon Fox in March 1994, and a Catholic woman Sharon McKenna in January 1993.
Police said the 40-year-old, who is being held at Antrim Police Station, is also being questioned about a number of assaults and a shooting incident.
A police spokesman said a total of 16 people had now been arrested under what they called 'Operation Ballast'.
He said 11 of those had been charged and four were the subject of reports to the Public Prosecution Service.
The operation was launched after former Police Ombudsman Nuala O'Loan's investigation into allegations of collusion between the RUC and the Mount Vernon unit of the UVF in north Belfast.
