Detectives investigating the murder of solicitor Rosemary Nelson have arrested two men in Belfast.
The pair were detained after three searches in the greater Belfast area, said a statement issued through Norfolk Police.
The men, aged 41 and 43, were being questioned at Gough detention centre in Armagh on suspicion of serious terrorist offences, it added.
Mrs Nelson was killed when a booby-trap bomb exploded under her car in March 1999.
Norfolk Deputy Chief Constable Colin Port was drafted in to head the inquiry into Mrs Nelson's murder shortly after her death.
The move was prompted by nationalist claims that Ulster security forces set up the killing in Lurgan, Co Armagh, which was claimed by loyalist terrorists the Red Hand Defenders.
The 40-year-old mother-of-two was a leading defence solicitor and acted for nationalist causes in Lurgan and Portadown.
Groups she represented included the Garvaghy Road Residents' Coalition and the Robert Hamill campaign.
The Port team has interviewed thousands of people but no-one has been charged with her murder.
PA