Engine-37 dispatched for gas Main Break. Arrived to find a high pressure gas main struck by water company, while cutting the street. 6" main that couldn't be shut down. The patch was going to have to be done Hot. COmpany 37, 36, 26, 74, station-24 & 34 for 1 Engine, 101, 103, 47 for the canteen. Companies stood by with charged water supply and handlines until the patch was made. Approximatley 6 Hrs