Power lines serving almost 2 million residents of the Crimea peninsula were damaged by a pair of explosions, cutting electricity for the region annexed by Russia last year.

Restoring service may take as long as four days, Yuri Kasich, deputy chief executive officer of Ukrainian state company Ukrenergo, said Sunday. Crimea declared a state of emergency after losing its electricity from Ukraine at 12:19 a.m. local time on Sunday, following an explosion on Friday and a second blast on Saturday.

Repairs were hindered by protests at the site of blasts. Police are investigating both explosions. “It was a mess at night when all the lights suddenly turned off,” Anastasia Kostyukova, 22, said by telephone from Sevastopol, Crimea’s largest city.

Read the article “Twin Ukraine Power Cable Blasts Leave Crimeans in the Dark” on bloomberg.com.