Power has been restored to nearly 99% of customers, LUMA Energy said in an update early Friday.

LUMA Energy gave an update at 5 a.m. on Friday morning, saying that almost 1.5 million people — or 98.8% of their customers — have now had their power restored.

“LUMA remains focused on completing the restoration and will continue work until all customers have service,” the statement from LUMA Energy read. “As of 5:00 a.m. on April 18, LUMA had restored power to 1,450,367 customers, representing 98.8% of the total, in less than 48 hours since the island-wide outage began.”

“With this progress, LUMA has met its initial projection of restoring service to at least 90% of customers by 12:40 p.m. on Friday,” the statement continued. “The LUMA Emergency Operations Center (LEOC) remains active, and teams continue to work quickly and safely to stabilize the system and restore service to the remaining customers.”

LUMA said that even though their work is nearing completion, some customers may continue to experience temporary interruptions due to limited generation.

Between 98% and 100% of hospitals in most regions have had their power restored along with most water and telecommunications systems and 100% of correctional institutions, said LUMA.

“The company continues to prioritize restoring critical infrastructure, including hospitals, water plants, airports, and emergency services,” LUMA said.

The private power company, which is responsible for power transmission on the island, said the massive outage appears to have been caused by a combination of factors, including a “failure in the protection system as initial trigger” and vegetation on a transmission line between the areas of Campaleche and Manatí, along the northern coast of the island.

This latest outage is the latest in a series of significant blackouts that have plagued the island in recent years, following the devastation of Hurricane Maria in 2017, which destroyed much of the power grid.

In December, Puerto Rico experienced an island-wide blackout on New Year’s Eve when an underground power line failure plunged the island into darkness for two days.

Power outages have become so common in Puerto Rico that many residents have installed solar panels and batteries in their homes and businesses. The ongoing instability of the power grid has also led to protests, with many criticizing LUMA, which took over power transmission and distribution in 2021.

ABC News’ Ahmad Hemingway and Doc Louallen contributed to this report.