question: The group that took responsibility for a mass shooting that happened in 1993 blamed it on an event carried out by who?
answer: Provisional Irish Republican Army
context: Title: Greysteel massacre
  Passage: The Greysteel massacre was a mass shooting that happened on the evening of 30 October 1993 in Greysteel, County Londonderry, Northern Ireland.  Three members of the Ulster Defence Association (UDA), a loyalist paramilitary group, opened fire in a crowded pub during a Halloween party, killing eight civilians and wounding thirteen.  The pub was in an Irish Catholic and Irish nationalist area.  The group claimed responsibility using their cover name "Ulster Freedom Fighters" and said that the attack was revenge for the Shankill Road bombing by the Provisional IRA a week earlier.
  Title: Shankill Road bombing
  Passage: The Shankill Road bombing was an operation carried out by the Provisional Irish Republican Army (IRA) on 23 October 1993 and is one of the most notorious incidents of the Troubles in Northern Ireland.  The IRA's intention was to assassinate the loyalist Ulster Defense Association leadership, who were to be meeting in a room above Frizzell's fish shop on Shankill Road, Belfast.  Two IRA members were to enter the shop disguised as deliverymen, then force the customers out at gunpoint and plant a time bomb with a short fuse.  However, when the IRA members entered the shop with the bomb, it exploded prematurely.  One of the IRA members was killed along with a UDA member and eight Protestant civilians.  More than fifty people were wounded.  Unbeknownst to the IRA, the meeting had been rescheduled.
  Title: Crisis actor
  Passage: A "crisis actor" is a term describing a hypothetical actor who participates in a false flag event such as a bombing or mass shooting simulated by the conspirators —usually government or corporate forces— in order to achieve some goal such as justifying increased government surveillance, disarmament of the population, or military action against blamed nations or groups.  Crisis actors are claimed in this context to play the part of bystanders or witnesses, emergency response personnel, and (with the aid of stage makeup) wounded victims of the attack.
citations: Shankill Road bombing Greysteel massacre