A major Puerto Rican power line repaired by the tiny Montana company Whitefish Energy failed Thursday morning, plunging almost all of the island, including parts of San Juan and other major cities, back into darkness.

Just 18% of Puerto Rico now has power, according to the island's energy utility, down from 43% before the line failed on Thursday, wiping out a quarter of Puerto Rico's power generation.

The line failure took out 25% of Puerto Rico's power generation, which was at 43% capacity just before the failure, according to the Puerto Rico Electric Power Authority (PREPA). Just 18% of the territory now has power, and officials did not have a clear timeline on when the power will be restored.

In a Facebook video, PREPA's director of generation, Justo González, said it was not yet clear why the line had failed. San Juan and the surrounding metro area, including Vega Baja, Arecibo, Barceloneta, Manati, Bayamon, were most affected by the outage, he said.

"The system hasn't completely gone out," González added. "The south is working. We have 18% power generation."



The power line, which runs from Cambalache to Manatí in the island's north, providing power to Puerto Rico's capital city, is one of the major sections of the power grid that Montana firm Whitefish Energy was working on as part of its controversial contract with PREPA.

In a Nov. 3 press release, Whitefish Energy said that its team had restored transmission lines and towers to "more than 10 miles from Cambalache transmission center to Manati (line 50100)."



But in a statement to BuzzFeed News on Thursday, Whitefish Energy denied that the outage was caused by any of the work it had done on that line.



"None of the issues reported today with the outage have anything to do with the repairs Whitefish Energy performed," spokesperson Brandon Smulyan said.



Another company spokesperson said PREPA is addressing the current problem without Whitefish Energy's assistance because the issue was not caused by the firm's work.

PREPA's handling of power restoration in the wake of Hurricane Maria has come under scrutiny after reports revealed that Whitefish Energy, a tiny firm with just two full-time employees, secured a $300 million contract without a competitive bidding process, and that it included contractor rates far higher than the industry norms. Faced with several federal and territorial investigations into the deal, PREPA cancelled the contract.



González said that PREPA is flying helicopters over the area where the line failed to determine the cause of Thursday's disruption, and is prioritizing restoration of power at hospitals, airports, water pump stations, and economic areas.

On Thursday afternoon, power at the emergency command center serving as a base of operations for territorial and federal government officials in San Juan experienced a power outage, according to reporters on the ground.