Latest information is that the Shankill bomber was a RUC informant yet MI5 took no action! why? The same UK security services, in particular GCHQ knew the phone numbers of the Omagh bombers yet did not pass them on to the police detectives. Why? Was this due to some sort of UK policy?
Remember it was at that time in the midst of the bombing campaign that power sharing with republicans came into vogue. Food for thought!