They also tried to find workers capable of reversing the plant's emergency shutdown and restarting the flow of gas, but showed little understanding of how the energy facility functioned, three plant employees who survived the attack said.

WSJ: Algeria Probes Possible Role of Local Workers in Attacks

The situation has evolved slowly but in a manner that was not anticipated by designers who had not assumed that electrical power to run emergency pumps would be unavailable for days after the shutdown.

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