On July 31, 2012, a massive blackout swept across northeast India. At 1 pm local time, a power line in the state of Madhya Pradesh became overloaded and tripped out. As the supply grid struggled to pick up the slack, other lines went down. By 1:03, a cascading series of failures had pushed the electricity supply grid into a state of chaos, resulting in the largest blackout in human history. More than an estimated 600 million people lost power temporarily as a result of the collapse.