A burst water main has cut off supplies to thousands of homes in west London.The incident near Holland Park Roundabout has sparked serious flooding in at least one nearby street, where residents have been rescued from properties overnight.Pictures showed cars submerged in water as Thames Water engineers try to fix the problem.Several streets have been closed, including part of Holland Park Avenue and the A3220 West Cross Route between the Northern Roundabout and the Holland Park Roundabout.