Spain’s high-voltage electricity grid suffered more power generation disruptions than previously known ahead of the country’s largest ever blackout, the government said.

Electricity is pulsing through Spain and Portugal again after a massive outage knocked out power in both countries on Monday. So too are questions.

Spain suffered several power glitches and industry officials sounded repeated warnings about the instability of its power grid in the build up to its catastrophic blackout on Monday. The government has ordered several investigations into the blackout.