((Wait, could you edit that a bit? I think you should follow on foot first before blasting straight through the floor to them. And besides, they're almost a mile away from you. You could follow his trail from the entrance to the Sewers and up a ramp through a sewage reservoir, and then either into the left or right tunnel of forked passage ways. In one of them will be the scene of a gruesome murder involving the combustion of a man's head, who's body is slumped against a ladder. You can climb up the ladder after investigating and into another reservoir, where at the end is a service tunnel with two Mafia gunmen guarding at the middle of it. Then there should be an elevator shaft Ite is using behind them. Good luck!))