Venezuela is facing its fourth nationwide blackout this year, which officials are blaming on a hostile “electromagnetic attack.”

The ongoing blackout has left nearly the entire country without power, including the capital Caracas.

About 94% of Venezuela’s telecommunications infrastructure has been affected by the outage, and internet connectivity is only running at 10% nationwide, according to Netblocks, a non-profit organization dedicated to tracking outages.

The exact cause of the outage remains unclear, but as with previous blackouts, officials are pointing the finger at hostile attackers, according to CNN. A government statement called the blackout “an electromagnetic attack,” though stopped short of providing details about who might have been behind the alleged attack or how it was carried out.