SAN JUAN, Puerto Rico (AP) — A blackout hit nearly all of Puerto Rico early Tuesday as the U.S. territory prepared to celebrate New Year’s Eve.

More than 1.2 million out of 1.47 million clients were without power, according to Luma Energy, a private company that oversees electricity transmission and distribution on the island.

It wasn’t immediately clear what caused the widespread outage or when power would be restored. Luma officials did not immediately return a message for comment.

In a post on X, Luma said it was in touch with crews and companies overseeing the generation of power in Puerto Rico to solve the outage. It said it would offer details as soon as possible.

A spokesperson for Genera PR, which oversees power generation, could not be immediately reached for comment.

Puerto Rico continues to struggle with chronic power outages blamed on a crumbling power grid that was razed by Hurricane Maria, a powerful category 4 storm that struck the island in September 2017.

The system was already in decline prior to the storm given years of lack of maintenance and investment.