(NEW DELHI) -- The lights are back on in India Wednesday after a massive power outage left more than 600 million people in the dark.
The blackout on Tuesday was due to the collapse of electricity grids in the northern and eastern part of the country. In all, 22 of India's 28 states were affected.
It followed another power outage that left some 300 million people without electricity for several hours on Monday. That outage was due to a failure with the northern grid.
Both blackouts crippled transportation, leaving hundreds of trains at a standstill and an untold numbers of cars stuck in traffic because there were no lights.
While states are being blamed for taking more power from the grids than they were authorized to do, an investigation is underway to determine the exact cause of the collapse.
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