Puerto Rico
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Most of the island of Puerto Rico was hit by a power outage early on Tuesday. More than 1.3 million people are in the dark.

Luma Energy said that it suffered a system-side blackout at around 5:30 a.m.

It said that while the cause of the outage is under investigation, preliminary findings point to a fault on an underground line.

It has activated emergency operations to restore power.

Luma says it will restore power to customers in phases but the full process will take 24-48 hours.

Puerto Rico has chronic power outages that are blamed on a crumbling power grid, the Associated Press reported.

Hurricane Maria in 2017 caused widespread devastation to the power distribution system. It has struggled to completely rebuild it.