Then the second engineer noticed strange movement in the overhead catenary wires above the eastbound train, and hit the emergency brake on his train, Mr. Cahill said.

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His client's decision to trigger the emergency brake lowered the train's speed to 45 miles per hour from 73 mph and likely saved lives, Mr. Cahill said.

WSJ: Probe of Metro-North Derailment in Connecticut Focuses on Rail

But I do say unreservedly, take the hands off the brake, let the train start.

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He said he didn't notice whether the driver tried to brake before hitting the other train.

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