WASHINGTON, Aug 16 (Reuters) - Three electric power transmission lines in Ohio probably caused the worst blackout in North American history, a top investigator said on Saturday.
"We now are fairly certain this disturbance started in Ohio," said Michehl Gent, president of the North American Electric Reliability Council, which was set up after U.S. blackouts in 1965 to promote electrical power stability.
"We are now trying to determine why this situation was not brought under control after the first three transmission lines relayed out of service," he said in a conference call to reporters.
The nonprofit group is working with utilities and federal, state and provincial authorities to determine the cause of the blackout that two days ago plunged an estimated 50 million people into darkness across the United States and Canada.