East Japan Railway Co. on Jan. 23 blamed human error for the power outage that stopped operations for about eight hours on the Yamanote and Keihin-Tohoku lines on Jan. 16, inconveniencing about 670,000 commuters.
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but the simple pressing of a button to release the safety device after construction was completed was not carried out on the Yamanote Line side.
by MagazineKey4532