SANTIAGO, Chile (AP) — Electricity providers across Chile scrambled to restore service Tuesday after a sweeping blackout plunged 90% of the country into darkness, stranding commuters, knocking cell service offline and paralyzing businesses and daily life.

The scale of the power outage appeared to take authorities off guard. The government declared a state of emergency alongside a mandatory nighttime curfew that will last until 6 a.m. Wednesday.

“Our first concern, and the reason for this announcement, is to ensure people’s safety,” Interior Minister Carolina Tohá said in announcing the exceptional measures. The ministry deployed thousands of soldiers across the country to help maintain order and enforce the curfew.

Mobile phone services blinkered offline. The world’s largest copper mine suspended operations. People complained of water shortages as pumps running on electricity stopped working. Emergency generators helped hospitals and government offices continue operating.