Squabbles between Spain’s minority government and opposition parties are muddling efforts to find out and explain what caused a massive blackout that left Spain, Portugal and parts of France in the dark on Monday.

While Spanish grid operator Red Eléctrica gathered millions of data points in a highly technical probe to determine what caused about two thirds of the country’s power supply to disappear from the grid, Prime Minister Pedro Sánchez drew the political battle lines of the blame game that’s already brewing, pushing back against claims that his government’s expansion of wind and solar was at fault.