 In July 1993, a Garda detective received information from a reliable source that on 15 May 1974, a meeting had taken place inside the Portadown Golf Club in connection with the Ulster Workers' Council (UWC) strike; the same informer added that a separate meeting was held in the club which was attended by Hanna and Samuel Whitten, a suspect in the Monaghan bombing.Hanna and Whitten were both regular customers at the golf club and were often accompanied by RUC officers.Tiernan said in his book, "The Dublin Bombings and the Murder Triangle", that the Monaghan bombing, which took place 90 minutes after the Dublin explosions, was executed by loyalists working under the direction of Hanna.