The attackers blew up power pylons in neighbouring Ukraine, which still provides the vast majority of the peninsula’s electricity.
Street lights were off, a state of emergency declared and a curfew imposed as local government struggled to cope with a power shortage that left key installations and the emergency services relying on back-up generators.
Hospitals were also left dependent on generators but in some cases these only provided enough energy to keep operating theatres and intensive care units functioning.
Water supplies were also disrupted as the power cut knocked out pumping stations. The blackout came at time of renewed tensions between Ukraine and Russia, which occupied and annexed the Crimea last year and has been involved in the war in eastern Ukraine.
Arseniy Yatsenyuk, Ukraine’s prime minister, announced a temporary ban on the delivery of all goods to the peninsula.
The ban will heap more woe on Crimea’s beleaguered residents who were warned by regional leaders that the blackout and power shortages could last a month.
“Unfortunately, we must inform our residents that, most likely, this period will stretch on for a while,” Sergey Askyonov, the Crimean leader said.
“We believe that we must prepare for the worst, meaning December 22.”
Meanwhile Dmitry Peskov, the Kremlin’s spokesman, called for Ukraine to take “vigorous steps” to restore power.
Just who carried out the attack, now the subject of a police investigation, remains unclear but suspicion has fallen on Tartar activists.
Crimea’s small Tartar community has accused Russia of using repression since Moscow took over the peninsula. In response its leaders have instigated an unofficial blockade of Crimea from the Ukrainian side as a means of putting pressure on the Russian authorities.
Yesterday pro-Tartar and right-wing activists prevented engineering teams from repairing the downed pylons.