 After the blasts the bombers fled from central Dublin in the scout cars and headed back north using the "smuggler's route" of minor and back roads, crossing the Northern Ireland border near Hackballs Cross, County Louth at about 7.30 p.m. Thirty minutes earlier, a fourth car bomb, delivered by a team from the Mid-Ulster UVF's Portadown unit, had exploded in Monaghan, killing an additional seven people.Samuel Whitten was allegedly the driver of the car.According to Tiernan, the driver of the green Hillman Avenger, which contained the bomb that had exploded in Parnell Street, was approached after the bombings by an RUC detective acting on behalf of the Gardaí.