The failure in the 230-kilovolt transmission line that runs from Arecibo to Manatí caused the loss of power mainly in the San Juan metropolitan area, including the municipalities of Manatí, Bayamón, Caguas, Guaynabo and Carolina.
The failure took place in the same transmission line that had been repaired previously by Whitefish Energy, a Montana firm recently under scrutiny for a $300 million contract to restore power on the island. The deal was later canceled by the Puerto Rico government after being publicly criticized by officials.
Authorities say they are expecting that service may be restored starting tonight in some of the affected areas; it could take about 12 to 18 hours.
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