I'm guessing a train arrived on time, first such event since the establishment of IE on the 2nd of February 1987, and gardaí were called in to investigate.
I'm not saying it was or not, but it possibly could have been Shamrock Rovers and Bohs skooligans having a knock, they've done it around that area before and with the big derby coming up on Friday it would make sense, I'll try finding out.;)