Relatives of some of those killed in the 1998 terrorist outrage travelled to Hillsborough Castle, Co Down to demand an explanation from Theresa Villiers as to why she had ruled out an independent probe into alleged state intelligence and investigative failings.
The families claim mistakes allowed the bombers to perpetrate the atrocity, and get away with it. The dissident republican attack killed 29 people.
While no-one has been criminally convicted of the crime, four republicans were found liable for the atrocity in a landmark civil case taken by some of the bereaved relatives and ordered to pay £1.6 million compensation.
Michael Gallagher, whose 21-year-old son Aiden died in the blast, said neither side gave any ground during the meeting. The families are set to take legal action, in the form of a judicial review, against Ms Villiers' decision.