The drivers of two tour buses were seriously injured in a collision on Ohio Drive SW this morning, near the Tidal Basin. The accident took place at 10:30 a.m. It looks like one of the buses was parked when the second bus crashed into it head-on, according to D.C. Fire/EMS spokesperson Pete Piringer. There were no passengers on board either bus, but one of the drivers was trapped and emergency crews were working to cut…